A/C Woes - Opinons/Guidance Welcomed

[06YarisRS]

DANG! May need yet another A/C compressor!

After my swap, obviously I needed to do some A/C work. I replaced the compressor with a used one and it turned out to have a noisy bearing, so back it went. The 'new' used one runs very quiet, but may have problems.

Below is my thought process.

As far as servicing the system, I followed the ChrisFix youtube video to the letter. I will say that there was some leaking around my manifold gauge fittings while filling with R134 despite properly tightening the fittings (firmly tight by hand/snug)

https://www.youtube.com/watch?v=Pdq8JAlct6s

The system held vacuum over night, so I was pretty sure it was leak free.

Put 1.3 cans of R134 (~16 oz) into the system.

Here is a pic of my readings - basically high presure on the LOW side, low pressure on the HIGH side. According to the tables below my pic, high pressure on the LOW side and low pressure on the HIGH side might suggest a faulty compressor.

Open to guidance. I would really like to do this myself, not be defeated and have to go to an A/C shop.


With Engine Off: ~55psi LOW side and ~42 psi HIGH side
With Engine Running: ~50psi LOW side and ~40psi HIGH side
A/C on and set to coldest position. Ambient temp was probably around 50F in my garage, so I had to do a bit of extrapolation.
https://i.imgur.com/sIR6SYC.jpg

https://i.imgur.com/JYJbPw4.jpg

[WeeYari]

I'll openly admit to not being much of an HVAC guy, but one possibility could be a faulty pressure sensor.

You have connected the pressure sensor to the compressor right? ;)

Sent from my EML-L09 using Tapatalk

[atomic_hoji]

You swapped an engine, an HVAC issue can't defeat you! :thumbsup:

The usual clause: I am also not an A/C expert - at all, by no means, lol.

But, a few observations.. Gauges are (generally) 1/2 the smallest subdivision for accuracy; quality, calibration, range (these are different range gauges) all effect gauge accuracy. To me, you have (basically) the same values LOW and HIGH pressure sides; it's equalized. I assume it is either the compressor hasn't run or it has a fault - an internal bypass or something is allowing pressure back through. Though in my experience with other types of compressor/pumps if a fault was the case you would see higher pressure on the HIGH side while it was running and it would equalize after shutdown.

When you have the engine running and the A/C on, are you sure that the A/C compressor clutch is energized and running the compressor? I ask because it may not run for one of the following possible reasons:

* A/C line pressure sensor detecting too low pressure, so A/C computer is cut-off A/C compressor run signal; i.e. not energizing the A/C clutch.
- A/C compressor or pressure sensor wire pins from engine harness to body harness are different (can't remember what you used for harness or if you checked the connections to the body differences or not..) so signal is not getting to the A/C compressor.
- A/C compressor or pressure sensor disconnected.
- usual suspects of poor connections or grounds.

I starred the first one as I have a hunch that may be the issue - this cut-off is how I keep my A/C system disabled at the moment since I haven't filled mine yet. The low pressure on the line sensor keeps the A/C clutch from energizing, or at least that's my recollection from months ago when I read up on it; those marbles have since been pushed out.. lol

If you hear it clunk, revs drop slightly, and A/C compressor pick-up then my point is probably moot. But if not, then maybe try the following check: disconnect the 2-wire connector at the A/C compressor, start the car, and select the A/C OFF. Check the SOL+ wire with a multimeter and see if it's powered. Do this again with the A/C ON and see if it's powered now. This should tell if the computer is requesting the A/C compressor to run.

-- Adam

[tmontague]

What was the ambient temps when you did this? Works best in hot summer temps. Iirc the fill is about 12 ounces not 16 but I could be wrong.

When I recharged mine it was winter, I disregarded the pressure readings as they will read low and not accurate when not in warm temps. I rechecked them once summer came and everything turned out fine.

My advice- fill the system to the proper amount after checking that there are no leaks. Leave it until summer and then recheck pressures or just check to make sure if blows cold, if it does then you're good to go

[WeeYari]

I thought you had a deal in place with a technician who came to your place at the beginning of the swap to discharge your a/c. When you were ready, he was going to return and recharge the system with your reclaimed gas.

Sent from my EML-L09 using Tapatalk

[06YarisRS]

You swapped an engine, an HVAC issue can't defeat you! :thumbsup:

The usual clause: I am also not an A/C expert - at all, by no means, lol.

But, a few observations.. Gauges are (generally) 1/2 the smallest subdivision for accuracy; quality, calibration, range (these are different range gauges) all effect gauge accuracy. To me, you have (basically) the same values LOW and HIGH pressure sides; it's equalized. I assume it is either the compressor hasn't run or it has a fault - an internal bypass or something is allowing pressure back through. Though in my experience with other types of compressor/pumps if a fault was the case you would see higher pressure on the HIGH side while it was running and it would equalize after shutdown.

When you have the engine running and the A/C on, are you sure that the A/C compressor clutch is energized and running the compressor? I ask because it may not run for one of the following possible reasons:

* A/C line pressure sensor detecting too low pressure, so A/C computer is cut-off A/C compressor run signal; i.e. not energizing the A/C clutch.
- A/C compressor or pressure sensor wire pins from engine harness to body harness are different (can't remember what you used for harness or if you checked the connections to the body differences or not..) so signal is not getting to the A/C compressor.
- A/C compressor or pressure sensor disconnected.
- usual suspects of poor connections or grounds.

I starred the first one as I have a hunch that may be the issue - this cut-off is how I keep my A/C system disabled at the moment since I haven't filled mine yet. The low pressure on the line sensor keeps the A/C clutch from energizing, or at least that's my recollection from months ago when I read up on it; those marbles have since been pushed out.. lol

If you hear it clunk, revs drop slightly, and A/C compressor pick-up then my point is probably moot. But if not, then maybe try the following check: disconnect the 2-wire connector at the A/C compressor, start the car, and select the A/C OFF. Check the SOL+ wire with a multimeter and see if it's powered. Do this again with the A/C ON and see if it's powered now. This should tell if the computer is requesting the A/C compressor to run.

-- Adam

I think you're right Adam that the A/C compressor has not cycled at all. I listened intently for the sound of it engaging and the rpm drop and it never did either. I was thinking that there might be an electrical issue and had planned to look at the wiring diagrams. I did wonder if there were pin inconsistencies between the Yaris and xD harnesses but will have to look to see which side controls the A/C. Since I didn't download all diagrams, I may go back to TIS for another 2 day membership and see if I can sort it. In the meantime, I thought about manually cycling the clutch with a 12V battery - out of my lawn tractor - to see if can get the compressor running and observe the gauge readings.

To your starred point about low pressure, when I started with my first can of R134, it was leaking out of the fittings. Maybe I just didn't get enough in there, but at the same time, I'd think 50 psi in the low side would be enough to trigger the compressor. That said, in the ChrisFix video, when he added R134, the pressure on the low side shot up way past my 50 psi.

I am going to start with your recommendation about testing the connector with a multimeter. I'll report back with my findings.

Thanks a ton, Adam

[06YarisRS]

I'll openly admit to not being much of an HVAC guy, but one possibility could be a faulty pressure sensor.

You have connected the pressure sensor to the compressor right? ;)

Sent from my EML-L09 using Tapatalk

Thanks WeeYari. Yes, all connectors were connected, but I'm not writing off any possibilities. Will recheck the connectors.

[06YarisRS]

What was the ambient temps when you did this? Works best in hot summer temps. Iirc the fill is about 12 ounces not 16 but I could be wrong.

When I recharged mine it was winter, I disregarded the pressure readings as they will read low and not accurate when not in warm temps. I rechecked them once summer came and everything turned out fine.

My advice- fill the system to the proper amount after checking that there are no leaks. Leave it until summer and then recheck pressures or just check to make sure if blows cold, if it does then you're good to go

Thanks Trevor. I was going by the Corolla which is 14.7 - 16.6 as my new compressor is larger. That said the Yaris does call for 370 - 430 grams (~13 oz) of R134, so I may have an overcharge situation. If I can get the system up and running and gauges are high, I assume I can release a bit.

[06YarisRS]

I thought you had a deal in place with a technician who came to your place at the beginning of the swap to discharge your a/c. When you were ready, he was going to return and recharge the system with your reclaimed gas.

Sent from my EML-L09 using Tapatalk

I did WeeYari, but the guy didn't seem very confidence-inspiring as he was asking me to get stuff, like the refrigerant, adapters for R134 etc. I thought I'd try myself. I told him I'd pay him for the evacuation. Almost wishing I'd gone with him, but if we had the same problem I'm having now, he'd have to come back again anyway. I think this is just a recent sideline for the guy, but I'm sure he knows a lot more than me.

[06YarisRS]

OK, some progress...

Well, the connector to the compressor was not seated :rolleyes:. It pulled straight out. I reseated it and it clicked into place. So, hopefully that solves the electrical problem. Will still compare wiring diagrams. However, both my LOW and HIGH side pressures are down to 30 psi from 50 since yesterday. Despite holding a vacuum overnight a couple nights ago, I may have a leak when the system is pressurized. :frown: I'm guessing that there was not enough R134 left to even fire up the compressor - if the wiring is good.

It seems to make sense to me that a system could hold a vacuum, but then leak when pressurized, however, I am a complete novice to HVAC. I did notice some corrosion on the high side port of the used A/C compressor I bought. The oil I put in has a dye in it, so if I recharge the system, maybe I can find the leak if there is one.

Steps (and, again, feel free to make suggested alterations):

1) test plug with multimeter as per Adam's instructions
2) grab an o-ring set and replace them
3) do another vacuum test
4) pick up another couple cans or R134 and try recharging (1 can)
5) monitor pressures over a few days
6) if pressure drops, get out the light and look for leaks.

Why are things never easy??? :laugh:

[atomic_hoji]

I think you're right Adam that the A/C compressor has not cycled at all. I listened intently for the sound of it engaging and the rpm drop and it never did either. I was thinking that there might be an electrical issue and had planned to look at the wiring diagrams. I did wonder if there were pin inconsistencies between the Yaris and xD harnesses but will have to look to see which side controls the A/C. Since I didn't download all diagrams, I may go back to TIS for another 2 day membership and see if I can sort it. In the meantime, I thought about manually cycling the clutch with a 12V battery - out of my lawn tractor - to see if can get the compressor running and observe the gauge readings.

To your starred point about low pressure, when I started with my first can of R134, it was leaking out of the fittings. Maybe I just didn't get enough in there, but at the same time, I'd think 50 psi in the low side would be enough to trigger the compressor. That said, in the ChrisFix video, when he added R134, the pressure on the low side shot up way past my 50 psi.

I am going to start with your recommendation about testing the connector with a multimeter. I'll report back with my findings.

Thanks a ton, Adam

While I was out installing my flow straightener in the intake this afternoon I double checked and my A/C line pressure sensor is on the HIGH side of the A/C system. That was my recollection and why I thought 50 psi might be too low. That being said, I believe you can overcharge a system too, so possible something is telling it there's too much in the system and giving it a cut-off. Do you have any OBD2 code thrown? I checked mine and I have no (A/C related! lol) codes being thrown, but the A/C cut-off is ON as I anticipated given I haven't charged my system.

If you find it is not getting a signal to energize the A/C solenoid and run the compressor that will at least tell you something is tripping it up. Giving it a nudge with a 12V external supply is a clever idea! I would just caution that you give it a brief bump and see what the pressures do - if the A/C system is giving you a cut-off, it's for a reason. :wink:

Did you make any changes on the connector that goes is a part of the engine harness that runs up to the main junction box in the engine bay? That's the connector that the wire for the A/C compressor runs from the engine side to the body side of the vehicle, and then on to the A/C computer. That'd be my starting place to look for wire harness differences.

Keep us posted!
-- Adam

[WeeYari]

Your psi is definitely down so low that, all things are good, your compressor will not get a signal to engage.

You need to get some UV dye into the system.

Sent from my EML-L09 using Tapatalk

[atomic_hoji]

Fastest "keep us posted" response ever! lol

Ya, a connector not seated could definitely be an issue. These things happen.. :laugh: Did you try firing it up and running it now that the connector is re-seated? That could have just been it.

I was going to comment that a vacuum holding test should actually be done for quite a while to really prove a system. I'm not sure what the standard is, but a 12 hr. hold to let it temperature stabilize, then a 24 hr. hold would be best - remember, the tiniest leak will eventually let the refrigerant out over time. New o-rings on any connection you had open is a very good idea. Are you torquing the fittings or snugging them up by feel or..? You made a comment about hand tight, but I don't imagine that's nearly enough for a pressurized system. I marked mine with a sharpie when I undid them and made noted of how hard they were (fingers to pull - hardly scientific..) to undo and re-did them to that mark, plus a ~1/12 turn to snug up.

-- Adam

[atomic_hoji]

+1 on the UV dye - good call WeeYari.
-- Adam

[06YarisRS]

Thanks gents! The dye is in there so I'm going to crawl under the car tomorrow and see if I can spot any leaks. I'm guessing that since it lost pressure, that hopefully it should be evident where it's leaking. The reason I didn't replace the o-rings initially was twofold: Toyota could not tell me which o-rings to use and when I called an A/C shop a while back, they said it is very rare to have to replace the o-rings. I was surprised by this.

Adam, the tightening I was referring to was the fittings on the manifold gauge set, not the A/C connections on the car themselves. However, I did just tighten those (the piping on the car itself) quite snug, not torqued to any spec. Also, I didn't make any changes in the fuse box other than the MAF power wire and the 3 speed sensor wires. I'll look at the wiring diagrams you suggest as well as set some time aside to d/l as many diagrams as I can. No doubt they'll come in handy in the future.

I'll go out tomorrow and see if my pressures are even lower. If so, I'll try and find the leak, fix it, do another vacuum test - only longer as you recommend, Adam, then see about evacuating the system and recharging.

[atomic_hoji]

+1 on surprised about o-rings, I feel like everything I read on A/C systems always says replace the o-rings. When I did the A/C compressor on my truck a couple of summers ago the warranty card actually said if the o-rings and drier weren't replaced at the same time it voided the warranty. Maybe a hype and in reality they're fine? Interesting..

Understood re: fittings - hopefully you find the culprit fairly easily. Fingers crossed it's a fitting and just needs a new o-ring at worst and it isn't the A/C compressor gasket.

edit: re - wiring, I didn't mean in the fuse box itself, just to be clear, I mean the connector that plugs into the fuse box - it could be different on the 2nd gens too. The fact your harness uses the same connector is a good sign. Was just wonder if for some reason the pins were different for ancillaries.

-- Adam

[06YarisRS]

Ah, sorry for my misunderstanding re the wiring. I will definitely compare wiring diagrams. Yeah, I really hope that the compressor isn't bad. If it turns out to be bad, I think I'll go with a reman one as opposed to used.

Thanks again. I really appreciate the help
Will keep everyone posted on my progress.

[dogsridewith]

Got a 91 Corolla about 2000 and the A/C worked at first but faded to nothing in a year or two. When I did the full system delete, I found at least one of those skinny O-rings mis-seated...it explained the dusty oil film that would appear on the passenger side headlight.

[06YarisRS]

Got a 91 Corolla about 2000 and the A/C worked at first but faded to nothing in a year or two. When I did the full system delete, I found at least one of those skinny O-rings mis-seated...it explained the dusty oil film that would appear on the passenger side headlight.

Thanks! I thought very briefly about doing an A/C system delete, but quickly dismissed the idea. I'm much more tolerant of cold than heat. I bet a delete would free up a tiny bit more power though, even when the system isn't engaged. Did you just get rid of yours because of the hassle of repairing/maintaining it?

[06YarisRS]

Starting over...

My pressures dropped again, suggesting a leak, but could be due to contraction of the gas as it's extremely cold here.

I have a vacuum on the system. I will be picking up an o-ring kit and a few more cans of R134 midweek. In the meantime, I'll monitor the vacuum as well as test to see that I have 12V at my compressor plug with the A/C switch turned on. Will also jack the car up and check for leaks that may have occured while I had the system (sort of) pressurized with R134.

I'll post a pic later of the vacuum. The pic below is about 20 minutes after a 5 minute vacuum. Holding solid at 30 vacuum.

https://i.imgur.com/26W6xe3.jpg

UPDATE: Lost about 10 psi vacuum in a few hours. Doing another test. I 'm not sure if my system has a leak or this cheap gauge set is leaking. Will check back in a few hours.

[06YarisRS]

Leaks...

In terms of A/C, these are probably considered massive leaks. My second vacuum test suggested that the system was leaking. I don't know how it held vacuum the first time I did it.

I plan to do the electrical testing tomorrow.

Big Leaks

https://i.imgur.com/VgZAKRC.jpg

Low side o-ring

https://i.imgur.com/g5ChGSd.jpg

High side o-ring

https://i.imgur.com/gZpl2gs.jpg

[dogsridewith]

Thanks! I thought very briefly about doing an A/C system delete, but quickly dismissed the idea. I'm much more tolerant of cold than heat. I bet a delete would free up a tiny bit more power though, even when the system isn't engaged. Did you just get rid of yours because of the hassle of repairing/maintaining it?
A/C delete during headgasket replacement at 150k on a car that was pretty well on the way to dying of rust. System was more of an add-on than w/ Yaris, which doesn't have the extra fan. Really cleaned up the engine compartment, which is busier than the Yaris' for other reasons too. (The 4AF series was originally an inline engine, and there was extra-bracket madness to make it work FWD, so the delete removed the belt and a bracket.) On A/C deletes I also remove the evaporator from the HVAC box, which makes the fan's output higher.
I do basically like/believe in A/C for cars, and would likely keep the Yaris' there and working.

re: your O-ring photos. Mine were thinner, the joint was different, and one of the rings was a bit rolled out of place.

[06YarisRS]

A/C delete during headgasket replacement at 150k on a car that was pretty well on the way to dying of rust. System was more of an add-on than w/ Yaris, which doesn't have the extra fan. Really cleaned up the engine compartment, which is busier than the Yaris' for other reasons too. (The 4AF series was originally an inline engine, and there was extra-bracket madness to make it work FWD, so the delete removed the belt and a bracket.) On A/C deletes I also remove the evaporator from the HVAC, which makes the fan's output higher.
I do basically like/believe in A/C for cars, and would likely keep the Yaris' there and working.

re: your O-ring photos. Mine were thinner, the joint was different, and one of the rings was a bit rolled out of place.

I get ya. Sometimes it's not worth spending the money and/or effort on repairing non-critical systems on older cars. I've vowed to get mine working. I think I'm going to replace the condenser as they're relatively cheap and mine has some dark spots along the top. It's entirely possible that it's just rustrpoofing that I applied that leaked down from the upper crossmember. But, I've got the front off and replacing the condenser should eliminate one more possible leak point in my diagnosis. Plus, replacing it looks like a pretty quick job.

[atomic_hoji]

Well, so much for troubleshooting - there's yer problem: refrigerants on the outside! Heh. Joking aside, on the bright side at least you have a good idea what the pressure drop is being caused by. Some new o-rings should help.

If you haven't already, as a quick note, especially if you decide to replace the condenser, if the system has been open a while a new drier desiccant bag is fairly cheap (as I recall) and will capture any moisture in the system after your refill.

-- Adam

[06YarisRS]

Well, so much for troubleshooting - there's yer problem: refrigerants on the outside! Heh. Joking aside, on the bright side at least you have a good idea what the pressure drop is being caused by. Some new o-rings should help.

If you haven't already, as a quick note, especially if you decide to replace the condenser, if the system has been open a while a new drier desiccant bag is fairly cheap (as I recall) and will capture any moisture in the system after your refill.

-- Adam

Haha, I hope that's my problem, Adam. I may be in need of a significant overhaul. I'm not putting a lot of stock in the compressor being good. However, if it is bad, I found a seller on eBay and messaged him about his rebuilds. Very, very thorough reconditioning and testing, so if I need a new one, I can get it for just over $100.00 USD.

The condensor - a TYC from Rock Auto (the Valeos on eBay were a bit too much) - comes with a dessicant bag already installed for $70.00 CAD or I can get a Denso for around $80.00 USD without the dessicant bag. Leaning towards the TYC at this point.

On another note, I was looking at new compressor hoses. I had to bend the tubing on the vacuum side but there's still a slight strain on the rubber hose part. Any more bending and I'm afraid I'll end up closing off the tubing. The problem is that there really isn't a direct replacement that would work for a Yaris/2ZR combination that I know of. I can get the discharge line hose assembly for the xD at Rock Auto but not the suction line assembly. I may put the suction hose assembly back in the vice - maybe with a large gauge wire inserted into it - and see if I can get a bit more bend without closing it off. The strain on it isn't that bad, but as the engine rocks a bit forward on deceleration, it will likely increase the strain.

[06YarisRS]

Replaced the two o-rings on the suction and discharge lines that attach to the compressor. Although I'm replacing the condensor this weekend, I thought I'd try a vacuum test for fun - always gotta be doing something on the car, right? :smile: Three hours and holding steady at 30 inches of vacuum. Now, hopefully that compressor will engage during the recharge. Wish me luck...:laugh: Oh, and I'll replace the o-rings that go on the condensor lines too. BTW, the new green rings are a tad thicker and have a tighter fit, but the lines went in easily, but firmly, with the o-rings lubed with PAG oil.

[06YarisRS]

New TYC A/C condenser has arrived. Pretty good for $54.00 CAD plus shipping.

My vacuum is still holding nearly 24 hours later, so I probably didn't need to get a new condensor. But, the old one is dinged up - lots of bent fins and a little exterior corrosion - from 12 years of use. So, I'll install the new one.


I plan to install it and recharge the system tomorrow.

https://i.imgur.com/aO7ZBeL.jpg

Mounted... I installed new o-rings, reattached the lines and it's sitting with vacuum on it now. About to go out and see if it held.

https://i.imgur.com/iQ90ldF.jpg

[06YarisRS]

Latest...

Checked the wiring diagrams on TechInfo and wiring at least to the compressor connector should be compatible. SOL+ is pin 7 (light green wire), SOL - (W/B wire) across Yaris, Corolla and xD Air Conditioning Amplifier Assembly. Having trouble finding the physical location of the Air Conditioning Amplifier Assembly. After I fixed the leaks, I recharged and still no compressor action. I'll test the compressor clutch assembly tomorrow with a jumper and the car battery. Either way, this compressor is toast. Under 45 psi on the low side, it's leaking fluid seemingly from the gaskets. Last time I waste my money on a junk yard A/C compressor. Should have known better. This is turning out to be a very frustrating job. Off to order a reman compressor... :rolleyes:

[tmontague]

That's tough luck with those compressors. I have purchased many things such as alternators from a local scrapper and have had good luck with them. That said one of the alternators has grease all inside of it and it almost caught fire when I installed it and ran the car. They claim they test all of their parts before they sell them - I call bs.

When it comes to engine swaps where a lot of things can go wrong, I tend to purchase reman'd stuff or brand new if my budget allows. This way it lowers the amount of things that are properly hooked up but internally faulty.

Obviously reman'd units I'm sure van also be faulty, but seemingly less so than scrapped parts.

[06YarisRS]

That's tough luck with those compressors. I have purchased many things such as alternators from a local scrapper and have had good luck with them. That said one of the alternators has grease all inside of it and it almost caught fire when I installed it and ran the car. They claim they test all of their parts before they sell them - I call bs.

When it comes to engine swaps where a lot of things can go wrong, I tend to purchase reman'd stuff or brand new if my budget allows. This way it lowers the amount of things that are properly hooked up but internally faulty.

Obviously reman'd units I'm sure van also be faulty, but seemingly less so than scrapped parts.

Good advice Trevor re: reman/new parts. I did order a reman last night and spoke with the outfit in Miami. They claim the use the shell and check every internal part, replace as needed and refurb the clutch. The also claim to test them after reman, but how would you ever know. The caveat is that there is no warranty unless installed (and documented by proof of receipt) by a certified A/C technician. I can understand that, I suppose. One upside of this remanfacturer is that their compressors come with a OEM approved factory fill of oil, PAG46 I expect, so one less step I have to fret over.

Anyway, I verified wiring diagrams on TIS and everything looked copacetic. This was confirmed by the following tests:

1) test commanded voltage with engine running. On C8 connector SOL+, I measure 2.62V with the A/C off and battery voltage (13.8V) with A/C turned on. So, the wiring looks good and the commanded voltage is being delivered.

2) Made a battery jumper and tested the clutch. Zero movement with direct 12V. This compressor sat on the shelf at the scrapyard for a long time and probably didn't even work when it came off the car.

So, as soon as my compressor arrives, I'll bolt that up, vacuum the system and recharge all whilst crossing my fingers. If nothing else, I'm learning a lot. :thumbsup:

[06YarisRS]

I applied intermittent battery voltage directly to the compressor and I don't even get a click. I powered it with and without the engine running. I'd hoped that if I cycled the clutch with the engine running, it would engage and I could see a boost in high side pressure. Nada, dead, nothing. I either have a bad field coil or the clutch is seized up. Regardless, this thing's spending the rest of it's useful - errr, useless - life as a boat anchor. Good thing I live right next to the ocean. :biggrin: Joking, of course. I'll keep it around for spare parts, or take it apart see what the guts look like.

It was just easier to cut the connector and connect the jumper. I have my soldering gun, heatshrink, split loom and tape ready to spring into action after the reman compressor is installed.

https://i.imgur.com/5egHu7e.jpg

[atomic_hoji]

Ah, bummer man. Sorry to hear about your luck with the A/C compressor. At least it's good to hear that the wiring is demanding the A/C pick-up and run, so once you get your reman. unit you should be able to pop it in, charge, and be off to the races!

-- Adam

[06YarisRS]

Ah, bummer man. Sorry to hear about your luck with the A/C compressor. At least it's good to hear that the wiring is demanding the A/C pick-up and run, so once you get your reman. unit you should be able to pop it in, charge, and be off to the races!

-- Adam

Yeah, I'm super happy about the wiring tests. My 'new' reman compressor arrived. I had a bit of buyer's remorse after paying for it as I read a number of reviews from Amazon customers - after the fact of course :rolleyes: (my fault) - that suggested that they just repainted junkyard compressors and shipped them out. As usual, eBay feedback for all positive transactions was so generic you couldn't tell if they were fake or not. The bad reviews of course mentioned specifics. Anyway, I had sent a couple of emails asking about their reman practices and, of course, no response. Once I told them I had contacted American Aftermarket Suppliers Association AASA) - one of their sponsors - whatd'ya know?...I got a response from the seller almost immediately. They claim that all of their used compressors are 'broken down, tested for leaks... and sealed if needed". The clutch is definitely reman as it has the 3 bolts that I've read are used to repair the clutches. For $99.00 shipping included, I'm not expecting factory performance, just no leaks, a functional clutch and some cold air. I can't expect spec pressures and performance for that price when a true reman from Denso or similar is several hundred dollars.

Anyway, fingers are crossed. I'll get at it again tomorrow. First, I'll test the clutch with my jumper cable, then, a long vacuum test. Then, later on Saturday - assuming a good air tight system - I'll draw a good hour long vacuum on it and try another recharge. I got some more documentation on spec pressures and other diagnostic information. Wish me luck.... :biggrin:

https://i.imgur.com/ErKR4qe.jpg

[tmontague]

Dude, I paid $110 usd for mine and all I wanted was a functioning compressor. Cross my fingers so far it's been flawless. At idle in mid summer the a/c isnt ice cold but this could he due to me having a slight under drive pulley and my a/c system may be slightly under filled.

I knew the a/c in my car was only temporary for a couple years so I wasnt concerned about a reman'd unit as long as it worked. I say install yours and test it out, chances are it runs fine and will last you st least a few years. Just dont let the compressor never turn off for 6 months so that it stays lobed.

Like you said, for the price you cant really beat it. Plus you have all the tools now so if it craps out in a few years just buy a new one and slap it back on. Most people never fix their a/c system when the compressor goes because it's well over a grand for the dealership to fix.

[06YarisRS]

For sure, man. I'll be hyped if it doesn't leak, provides a bit of cool air and isn't noisy. There's no really knowing what they did do to it, but it actually looks great from the outside and I think they had the manifold cover off - probably to replace the seal/gasket - as the bolts holding it on are hex heads vs the OEM standard bolt. At $99.00 shipped, it's as good a possibility of a functioning unit as you're gonna get as they're in that area used, dirty and corroded from a local scrap yard. And, apparently this one comes with a factory load of new PAG oil, so that's one less worry. Problem is the chance you take can be a costly one. I'm already into $60.00 in R134, not to mention a seal kit. But, like you say, a dealer or A/C shop would be a heck of a lot more.

And your right - I do have all the gear needed now. I think if it fails, I might have a go at rebuilding my other one, mainly for the learning experience. Re: running the A/C system regularly - I do this every few weeks year round. It's definitely best practice, lol, from what I've been reading.

[06YarisRS]

Another fail! I'm ready to pack it in and take it to an A/C shop. I installed the new compressor, new o-rings, the connector shows battery voltage with the A/C switch on (and lit), vacuum test held 30 inches over night and I'm having the exact same issues. It's like the compressor won't run. When I first started adding the R134, the compressor made a few clicking sounds and I got excited hoping to see the low side drop a bit and the high side rise. Nothing... As you can see in the gauge pic, the low side is about 22 psi and the high side is about 65. The Yaris calls for around 13 oz and the Corolla about 15. I added about 14 oz and never as I was adding it (to the low side, with the AC turned on) did the high side rise past 75 or 80.

I've got hours and hours into this and it's downright depressing.

Current pressures:

https://i.imgur.com/w0MpegZ.jpg

Reman Compressor Installed

https://i.imgur.com/n0PPEOS.jpg

[WeeYari]

Have you tested for a signal coming from the pressure switch?

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[06YarisRS]

Have you tested for a signal coming from the pressure switch?

Sent from my EML-L09 using Tapatalk

I assumed, WeeYari, that since I was getting battery voltage at the compressor connector to trigger the clutch with the A/C switch on an illuminated that everything from an electrical standpoint was ok. With the connector removed, the A/C light will not illuminate. I'll dig deeper into this. Thanks!

Edit: The wiring at least looks the same. I guess I'll look into figuring out how to test that sensor.

https://i.imgur.com/TE42OyF.jpg

[WeeYari]

I think that with a/c on you will always get power to the compressor. It is up to the pressure sensor to send the signal to engage the clutch....I "think"...*shrug*

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[atomic_hoji]

Bah, frustrating! Sorry to hear it hasn't panned out yet man..

Let it sit for a few hours and see how it settles out.. then try your voltage checks again to see if it's asking for the A/C compressor.

edit: No, no epiphany - at least on the 3rd. gen - the ground is hardwired.. BUT - fuse check?! There is a 7.5A fuse supplying the A/C amplifier; looks like fuse panel inside the car.

Cleared codes and everything before trying? Maybe the ECM or A/C amplifier is giving a cutoff because it has the prior code stored of low pressure?

Just throwing some things out there.

-- Adam

[06YarisRS]

Thanks guys! I did some more tests before heading out of town for son's hockey game. Just got back in from the garage and the low and high side are both at 50. When I engage the A/C switch, the rad fan cycles on and off at very high speed about every 20 seconds or so. For a minute it seemed like the engine was going to stall - revs dropped down - under load from the compressor, I suspect - and then it recovered. There was no change in the gauge readings. Also, if I remove the connector from the low side pressure sensor, the fan does not turn on and off as when it is plugged in.

After the charge, I directly connected my jumper cable from the battery to the compressor pins with the engine running. There was no change in the gauges and no drop in idle either.

When I first started introducing refrigerant this morning, the suction pipe became quite encrusted with ice even though I introduced the refrigerant slowly, monitoring the gauges. I thought maybe things froze up.

I will try your recommendations. I am also going to have to try interpreting the diagrams to see if how dependent the compressor is on the other parts of the system. But what gets me is if I apply direct 12V power from the battery, the compressor/clutch seems to do nothing.

I'll keep plugging away.

[tmontague]

So either your compressor is bad again (doubtful) or the way you are jumping it is not a sure guaranteed way to run the compressor (only ewd's would show that)

Or the way you are adding in refrigerant is not working property. Either it's being done wrong or something wrong is going on. Possibly an issue with manifold gauges?

[06YarisRS]

So either your compressor is bad again (doubtful) or the way you are jumping it is not a sure guaranteed way to run the compressor (only ewd's would show that)

Or the way you are adding in refrigerant is not working property. Either it's being done wrong or something wrong is going on. Possibly an issue with manifold gauges?

Thanks Trevor. I'll post in a sec....

BTW, I could not see any differences in the schematics between the 2008 xd and my '06 Yaris.

[06YarisRS]

SUCCESS!!! This may sound weird, but one of the parents of another kid on my son's hockey team suggested gently tapping the pressure sensor port. He said he'd seen it work if for any reason the switch is stuck. I did this a few times. So, it's either that or something equalized as it sat (as Adam suggested) but it's functional now. I put the gauges on my windshield and watched the pressures. At first I was getting around 50 on the low side (supposed to be 22 - 36) and it wanted to spike up about 250 - 275 on the high side (supposed to be 199 - 228 @1500 rpm) - a slight overcharge situation. I let a little R134 out of the low side and it's running around 40 Low side and 210 - 215 high side. I'll let a touch more out tomorrow. I warmed up my garage up as best as I could and then the inside of the car - very toasty in there. Then, I engaged the A/C with recirculation. Air is icy cold. I'll grab a thermometer tomorrow and see what temps I get.

I gotta say, there are a lot of variables with this A/C stuff. As you mentioned, Trevor, the gauges...I questioned them a few times.

I'll also monitor pressures over the next couple weeks to see if the system is completely tight.

[WeeYari]

*clap*

(how many times have I said pressure sensor)

Hope she holds out for you.

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[tmontague]

*clap*

(how many times have I said pressure sensor)

Hope she holds out for you.

Sent from my EML-L09 using Tapatalk

Ya kudos to you, sometimes its the simple things and you picked that out from the get go.

Good to know about the tapping solution though, may be useful in the future

[06YarisRS]

*clap*

(how many times have I said pressure sensor)

Hope she holds out for you.

Sent from my EML-L09 using Tapatalk

Yup! It does seem you were right, WeeYari. My apologies for not initially mentioning your suggestion. Though, I wouldn't want to stake my reputation - as questionable as that is :laugh: - on that being the cure for my particular system. But, other than sitting/time, it does look like the only other manipulated variable in this situation.

I'm fully prepared to have the system slowly discharge. You know it has to happen. The area I'll be watching is the tube connection at the firewall. I remember it going in very snug when I reassembled, but it is the only connection for which I did not install a new o-ring.

I was very happy to see this little high side sensor window nicely full of R134. In my excited state, I forgot to snap a pic of the gauges showing proper pressure. Will post one tomorrow.

If anyone is bored and happens to have a manifold gauge set kicking around, it would be neat to see the readings and a comment on how effectively their system works. I'm guessing the optimal settings - for a stock Yaris would be the numbers I mentioned a post or two back. It would be interesting to know how slight differences in pressure influence the functionality.

https://i.imgur.com/cKfQUqP.jpg

Thanks WeeYari!

[tmontague]

I will test put my pressure's down the road and let you know
I have a feeling mine is slightly low on r134, I'll probably top up at the same time. Only problem with mine is at idle ons crazy got day it is not that cold. Still cool bit not nearly as cold as when the car is moving and the revs are up

[06YarisRS]

I will test put my pressure's down the road and let you know
I have a feeling mine is slightly low on r134, I'll probably top up at the same time. Only problem with mine is at idle ons crazy got day it is not that cold. Still cool bit not nearly as cold as when the car is moving and the revs are up

Thanks, I look forward to it.

No doubt your underdrive pulley is affecting that as you mentioned earlier. Practically every car I've owned drops cold air at idle and increased revs and more air through the condensor brings it back to life. Think I'll check out my other Yaris and minvan as well. Gotta make those gauges pay for themselves. LOL.

How much does your A/C affect idle on the 2ZR? Mine seemed to labour slightly, until I removed a bit of the refrigerant. It still slows a few rpm when I engage A/C. I'm getting the impression that A/C systems are more power-robbing than I had initially thought.

[atomic_hoji]

Woo! Nice - glad it's worked out for you. Good call by WeeYari.

-- Adam

[06YarisRS]

Woo! Nice - glad it's worked out for you. Good call by WeeYari.

-- Adam

Yes! I have a new theory, unsupported by EWDs or anything wiring related at this point: The last time I introduced R134, it was cold in the garage. As I mentioned the suction tube became heavily ice encrusted. Maybe the pressure sensor/switch froze up. Tapping it and letting it sit allowed it to open and become operational. So, I'm going with WeeYari's pressure sensor suggestion as being the problem.

Merry Christmas, gentlemen! And, as always, thank you for the invaluable help.

[tmontague]

How much does your A/C affect idle on the 2ZR? Mine seemed to labour slightly, until I removed a bit of the refrigerant. It still slows a few rpm when I engage A/C. I'm getting the impression that A/C systems are more power-robbing than I had initially thought.

The engine definitely has a noticeable load difference on it. For a small 4 banger it is quite a bit of draw on its overall power. I know dyno's online have shown anywhere from 3-6hp draw iirc. On a low powered engine this is a large percentage of the overall power output so it is more noticeable.

I'd purge a bit of your r134 out but I dont think you need to release much

[06YarisRS]

The engine definitely has a noticeable load difference on it. For a small 4 banger it is quite a bit of draw on its overall power. I know dyno's online have shown anywhere from 3-6hp draw iirc. On a low powered engine this is a large percentage of the overall power output so it is more noticeable.

I'd purge a bit of your r134 out but I dont think you need to release much

Yeah, it's significant. When I removed my manifold gauge high side port today, I noticed a bit of refrigerant bubbling around the bottom of fitting. I think the schrader valve is in a little fitting that may have loosened a bit after opening and closing the ports. I tightened it a bit and the bubbling stopped but the little sight glass seemed to not be full as before. My low side is reading 40, but the system didn't kick in today. I may have lost a little charge but I don't think any air was introduced into the system as it's still under pressure. I'll keep the system in its current state and in the spring, test it. At least I know all the components are functioning properly now - or at least I think they are.

[WeeYari]

Your pressure sensor may be finding its place onto your shopping list. Mine failed in 2014. I lived without a/c until last year when I finally diagnosed my non-functioning a/c.

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[06YarisRS]

Your pressure sensor may be finding its place onto your shopping list. Mine failed in 2014. I lived without a/c until last year when I finally diagnosed my non-functioning a/c.

Sent from my EML-L09 using Tapatalk

You are probably correct. They look fairly inexpensive, but would necessitate another discharge, vacuum and recharge. I think I'll do this in the spring/summer. I'll probably replace the schrader valves too as well as the o-ring at the firewall (expansion valve?).

[06YarisRS]

Your pressure sensor may be finding its place onto your shopping list. Mine failed in 2014. I lived without a/c until last year when I finally diagnosed my non-functioning a/c.

Sent from my EML-L09 using Tapatalk

Just ordered a Denso on eBay for ~$11.00. Do you happen to know, WeeYari, if the schrader valves are just standard R134 valves and if they are both the same size? Also, I think I'll need a special tool. I have one for tire schrader valves, but it may be different.

[WeeYari]

Good price on the sensor. New? You wouldn't believe the cost of one through Toyota Canada. North of $600. Why is their price so high? Only available as part of a tubing replacement bundle believe it or not.

As for your Schrader valves, I can't imagine any reason for replacement. They sit there for life under their little protective caps.

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[06YarisRS]

Good price on the sensor. New? You wouldn't believe the cost of one through Toyota Canada. North of $600. Why is their price so high? Only available as part of a tubing replacement bundle believe it or not.

As for your Schrader valves, I can't imagine any reason for replacement. They sit there for life under their little protective caps.

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Yes, it's new, unless I'm being scammed. lol.

https://www.ebay.com/itm/For-A-C-Pressure-Switch-Sensor-Denso-for-Lexus-GX460-IS300-Toyota-Highlander/362366975539?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

I think it was mainly leaking around the base of the fitting that holds the schrader valve (turning the manifold gauge dials may have loosened it), though I thought I saw a little bubbling inside the valve toward the base. I gave it a little tap on the top of the schrader valve and it seemed to seat and there were no more bubbles. They may be fine, but I thought since I have to discharge the system again to replace the sensor, I figured I'd do the schrader valves at the same time.

[WeeYari]

I went with a somewhat more expensive listing. Can't remember why but I suspect it was because shipping on the cheaper ones was stupid high.

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[dogsridewith]

often find valve cores loose in schrader stems

[06YarisRS]

often find valve cores loose in schrader stems

Thanks. I am going to pick up an A/C schrader valve tool as well. May try just snugging them up a bit.

[06YarisRS]

Our local APM auto parts store actually had an A/C schrader valve tool - and this after calling half a dozen shops in the city 80 kms away and no one having one. $6.00 + tax out the door. I'm heading across the border tomorrow to pick up my Denso sensor, 2 cans R134 and the schrader kit.

Current plan is to wait for a warmish day, get my garage up to 65 - 70F, aim my big fan at the condensor and try again. I'll evacuate, replace the o-ring at the expansion valve, the schrader valves and pressure sensor. Then, a lengthy vacuum test. Finally a recharge quantity of R134 (~ 13 oz) and pressure tests based on ambient temps.

From both what Trevor said and what I've read, this is work best not done in winter. I wonder if my vacuum tube would have iced up so badly in warmer weather.