View Full Version : Alternative to Rod Knock?!
atomic_hoji
03-03-2019, 08:21 PM
Throwing this post out there in hopes someone has a clever idea of an alternative to chase versus the unfortunate reality of what is most likely a rod knocking thoka-thoka-thoka as the car idles..
Quick background is that car had pinky, nasty discoloured junk in the oil a while ago. Was in a pinch, so I changed it out with some old 15W40 Shell Rotella T I had sitting on the shelf. Ran that and dumped it within a couple hundred kilometers to clear out the pinky nasty. New, fresh Penzoil 5W30 in it. No discolouration visible in the valve cover, but found it was still appearing on the dipstick a bit. Figured it was leftover and didn't have time to deal with it the past few weeks due to other life things. Noticed after we had a burst of wicked cold weather that the car was noisy at idle. Too busy, ignored it to get through another exam I had this past week. Had to run into work today and when I got home it's very noticeable now. Weather is warm and cold back and forth and I was really hoping as the weather changed it would go away, but with no luck - it's just getting worse..
Tried loosening the serpentine belt to see if it was a pulley driven noise, but no - noise is still there with belt off. Car starts, revs a bit, drops to idle, and thoka-thoka-thoka noise appears..
I've had no experience first hand with rod knock myself, so I'm using the ye olde interweb videos to compare the sound - which while there is a variety of different nasty sounds of rod knock in YouTube videos, they are all eerily close to what I'm hearing. :frown: Only other thing I've heard in person that's similar is a 2UZ when it gets a crack in the exhaust manifold - I feel like that's more of a ticka-ticka-ticka though... If it IS the manifold it's all the more reason to chase a long-tube. :wink:
Have to limp through to March Break when I've put in to take the week off. Fingers crossed I can find something else to explain the issue; e.g. manifold.. Of course, first step of troubleshooting will be to check the oil for metal. Worst case will be either find another low'ish mileage 2ZR to swap - and flip the Valvematic head or get another ECM for an -FE - or yank it and slam the 1NZ back in.. :cry:
Fingers crossed you clever folks have some good ideas to chase... :biggrin:
-- Adam
dogsridewith
03-04-2019, 08:31 AM
What is pink but Toyota coolant?
Coolant in your oil. Possible causes, none are good:
Defective or deteriorated seals
Blown head gaskets
Improperly torqued head bolts
Thermally warped or cracked cylinder heads
Cracked block or cylinder head from frozen coolant
Improperly machined head and block surfaces
Corrosion damage of cylinder liners
Cavitation erosion/corrosion of cylinder liners
Electrochemical erosion
Damage or corroded cooler cores
Water pump seal failure and weep-hole blockage
tmontague
03-04-2019, 01:28 PM
I cant think of anything other than what you have stated. Possible oil contamination causing a a spin bearing the cause however could be anything BZ stated above.
FWIW during the cold months I notice water mixed with oil on the tip of my dipstick (dont say that out loud). It isn't pink colored however and it is the same stuff that shows up in my catch can when I dump it.
This is likely due to my commute to the gym and work only getting my oil up to 168F so the water doesnt boil off until I do a longer run in the highway.
Not sure if this is what you are experiencing, but chances are it's not seeing as yours was pink compared and you have a noise.
suprf1y
03-04-2019, 03:10 PM
It's impossible to diagnose without actually hearing it but from your description it sounds like it goes away when you rev it and comes back on idle? If so that doesn't sound like a rod knock.
atomic_hoji
03-04-2019, 07:36 PM
Thanks everyone for the replies! :thumbsup:
I appreciate where everyone is coming from on the coolant possibility. I said 'pinky', I should have been more specific - a 'pinkish tinge' to it. Not to say it isn't still possibly the source of the issue, but I had (maybe hoping) chalked the colour up to a reaction with additives in the oil. Now, however, according to my wife who provided a 'peer check' for me - since I have utterly useless close-up vision - she doesn't think it's pink at all. Apparently what the hell do I know?! lol
...
FWIW during the cold months I notice water mixed with oil on the tip of my dipstick (dont say that out loud). It isn't pink colored however and it is the same stuff that shows up in my catch can when I dump it.
...
lol! Well played, sir.. But, that's very interesting - that is exactly what I'm finding.. The first time, when I changed it out immediately, it was definitely water up in the valvetrain and I knew it was condensation from leaving the vent hose disconnected (the hose had water droplets come out of it..). Since then, I have been assuming it was leftover contamination in the oil - it has had a cocktail of oil through it in a short time. I've never run into this issue on any of my prior vehicles.. As you said, short commute - maybe 10 minutes driveway to parking lot - so the car doesn't warm up really..
It's impossible to diagnose without actually hearing it but from your description it sounds like it goes away when you rev it and comes back on idle? If so that doesn't sound like a rod knock.
Regarding noise going away - when driving it becomes hard to hear just in part because of wind and road noise; it's getting worse, but isn't like a clapped out pre-combustion chamber diesel.. lol I've always popped the hood, gotten out of the car, and listened at idle so I had my wife come out and give me a hand when I got home from work today and had an interesting result.
Still partly warm from driving home, I got my wife to start the car and 'poof', no bad noise.. of course - she's not an auto mechanic by trade, no. lol Let it idle to warm-up and had a listen. When I asked my wife to rev the engine a bit, she stepped on the clutch and brake, and whammo - noise started right up.. I got her to do a combination of brake and clutch and it wasn't reliable to go away / come back. BUT, it's the first time I've heard it audibly when I've gotten home and then had it go away. Annoying, but good news?! I don't imagine if it was a connecting rod that the noise would go away at all? Adding revs to it speeds up the noise as expected, and eventually the volume of the engine and speed it starts to blend in and become difficult to hear - almost turns into a smoother whir-whir-whir instead of a snappy, metallic toka-toka-toka.
Sound-to-text technology at it's finest here.. hah. One of these days I'll figure out how this YouTube thingy works. :rolleyes:
Never-the-less, I appreciate the replies from everyone, thanks! Makes for a few ideas to have a look at, and (oddly) explains that goop on the dipstick is apparently a common 2ZR thing..? Sam's just across the way and probably has the same sort of weather we're getting - I wonder if his dipstick has the same trouble? Maybe a bit of a personal question.. :biggrin:
-- Adam
tmontague
03-04-2019, 10:29 PM
I'm not your guy to detect rod knock as I have never had the issue myself, but I would expect rod knock to never go away - so possibly good news.
So it came back when the brake and clutch were applied? Does anything change the sound ie: clutch depressed, brake depressed etc...? I had a weird chirp in my engine which turned out to be a slave cylinder/fork junction that needed re greasing. It was vibrating and chirping when the engine vibrated. Also I had a terrible noise when I threw in an aftermarket 1nz starter as the pinion gear was an extra mm thicker and causing light interference with the flywheel.
Things to think of although not a likely problem in your case. At this point I would try and do anything you can to effect the sound. Hopefully something comes up and you find your solution. I find a spun bearing really hard to believe in a 2zr with virtually no heard of issues like that online.
FWIW a long highway drive out to the border (about 50mins) held at 3.6k rpm in about -10C only let the oil get to 199F. It still isn't hot enough to boil the moisture out of the oil. It will help some, but not get it all. After seeing my results of a relatively short commute of 20km each way most on highway, I would highly recommend a once per week highway burn of at least 30 mins spent going 120km/h. Preferably on the warmest day of the week.
It may be overkill as I'm sure there are not many 2zr owners out there who do this and still drive short trips without issues. However, moisture seems to build up fast in these engine blocks so it certainly won't hurt.
atomic_hoji
03-04-2019, 11:30 PM
All suggestions helpful at this point, lol. In my experience random rattles and sounds are usually a terrible p.i.t.a. to chase down when something isn't obviously broken.. The more ideas to have a look at and rule out the better.
Interesting about the oil temps - I would have thought cruising open highway for even a half hour trip would have gotten oil temps up enough to clear any moisture. Guess I need to get her out and stretch the legs more often.
Actually, in speaking to my wife tonight just now she said she took her foot off the brake - which I question why she was removing her foot from the brake when I was asking her to increase the revs; just in case the gear shift got leaned on or something... but I digress. lol
I'm not really ready to believe that it has a bad bearing already either, that's why I thought I'd throw it out there and see; half don't want to deal with the hassle and half is my new-found love of the 2ZR :biggrin: I'm not gentle with my car by any means, but given you guys who are tracking the cars and putting them under way more stress than what I imagine a cold start and a heavy foot would be, I would be surprised. Fortunately, I haven't had to deal with a bad rod either, but when idling away it really sounds like clunky bang around in the engine itself - which is why I went after the pulley driven stuff quickly first thinking maybe a belt issue or something - so brain just went to rod knock given the sound after that proved unsuccessful.
Have to shuffle some vehicles about and get a look at it next week. At least I have a number of ideas to chase now. Have to have a think on brake thing... opens up vibrations in the transmission maybe? Brake holds the driveshafts, let go and they (one or both..?) vibrate... that leads down a slightly better road then a spun bearing.
We shall see!
-- Adam
I know you are focused on the tapping, but the real present danger here is the pink toyota antifreeze in you crankcase. My $0.02 worth.
bob225
03-05-2019, 09:14 AM
Where to start,
Any issue starting the car ?
Have you done a compression test?
Have you done a Hydrocarbon test?
Have you listened to the engine with a stethoscope ?
Any OBD2 codes ?
2018 is still under warranty, Take it back to the dealer, Its their problem
tmontague
03-05-2019, 11:03 AM
Where to start,
Any issue starting the car ?
Have you done a compression test?
Have you done a Hydrocarbon test?
Have you listened to the engine with a stethoscope ?
Any OBD2 codes ?
2018 is still under warranty, Take it back to the dealer, Its their problem
:laugh: he's swapped a 2zrfe in it, the dealership wouldn't know where to start
Is that true? 2018? I guess I missed that. Why in God's name would someone do an engine swap on a sub-one year old car? Totaled?
atomic_hoji
03-05-2019, 06:37 PM
...
Any issue starting the car ?
Have you done a compression test?
Have you done a Hydrocarbon test?
Have you listened to the engine with a stethoscope ?
Any OBD2 codes ?
2018 is still under warranty, Take it back to the dealer, Its their problem
Appreciate the follow-up. No issues (starting, running, or codes) with the car other than the noise; compression test not terribly long ago was aces across the board; no HC test; don't own a stethoscope, but feel like it's a good investment - I'll have to look those up.
Is that true? 2018? I guess I missed that. Why in God's name would someone do an engine swap on a sub-one year old car? Totaled?
As Trevor noted, I'm not sure the dealership will look kindly on my puttering about with it.. The mechanics might think it's fun, but I'm sure I know what the answer will be regarding warranty. lol I mean, it's still a Toyota engine under 3 year and 60,000 kms...! Still no, huh? Well fine.
Drive a 2ZR swap and you'll understand why it was such a motivator to tinker. :biggrin: Also, the swap hadn't been done on a 3rd gen. or with a Valvematic, so I figured I'd might as well dabble..
-- Adam
tmontague
03-05-2019, 07:06 PM
Is that true? 2018? I guess I missed that. Why in God's name would someone do an engine swap on a sub-one year old car? Totaled?
Same reason anyone modifies any car. I modified and 2zr swapped my yaris that has a book value of $4-5 grand. Anyone could say that is silly as well.
Most of us did it for the challenge plus the extra performance and originality. It's a low cost car so it frees up some extra cash to do things like that
myfirstyota
03-05-2019, 07:58 PM
FWIW, and it's not worth much, lost an engine to POSSIBLE rod knock. My old 300M special. The engine was silent till about 480,000km at which point it developed a slight tick (religious 5k oil changes). It gradually got louder till 534,000. Then on Christmas eve the tick became noticeable while driving down the hiway. I thought I should probably get my boy home. Just after flipping around, the tick turned to a thunk. Now I say possible rod knock because of the noises it was making. You'd have thought it was In time with the rpm. And it was nasty. In the end, he just didn't have it in him and died 2km from home. I never investigated because I had no intention of replacing the engine in a car with over half million km. But hadn't owned a yaris at that point lol
If you are getting coolant in your oil, not good. But I'm gonna have to go with "too new and no real reports of those problems" idea.
myfirstyota
03-05-2019, 08:00 PM
Same reason anyone modifies any car. I modified and 2zr swapped my yaris that has a book value of $4-5 grand. Anyone could say that is silly as well.
Most of us did it for the challenge plus the extra performance and originality. It's a low cost car so it frees up some extra cash to do things like that
The challenge
bob225
03-06-2019, 09:27 AM
I missed the 2zr bit, if its bottom end, throw another engine in it there are plenty around and there cheap, you will get it done over a weekend
As Tavarish says "I am the warranty" lol
edit. Send a oil sample off to be analysed
tmontague
03-06-2019, 11:06 AM
"I am the warranty" Haha I love that
atomic_hoji
03-19-2019, 08:27 PM
Thanks for the replies everyone.. got busy over the March Break week being off with the kids, friends visiting, etc..
I did change the oil a week or so ago on the weekend. Absolutely nothing of note in the oil that came out. Has a few thousand kilometers on it, so it was a bit darkened, but otherwise looked fine - no pink/whatever goop/sludge/etc.. no weird film or discolouration.. no dirt/particulate/chips/chunks/etc.. either. I'll get the sample sent off just to confirm, but at a macroscopic level the oil doesn't give me reason to worry.
Also, I have a particularly terrible memory for "be gentle until you know what the problem is". :rolleyes: A number of times in the past couple of weeks I've caught myself honking on it on the drive to/from work - usually coming home, because leaving work is so much more enjoyable than going to work.. lol If it's a bad rod rattling around in there I don't imagine it's going to handle 5000 rpm too many more times before it explodes and makes a peephole in the block.
...
If you are getting coolant in your oil, not good. But I'm gonna have to go with "too new and no real reports of those problems" idea.
No, I agree, but fortunately the pink'ish (or not pink at all, depending who's checking..) goop on the dipstick seems to be explained by Trevor. Now that I've changed the oil and see nothing to note, I'm suspecting it's not a coolant leak. And ya, I haven't read much in the way of trouble, especially at low mileage, with the ZR family of engines. That's part of why I thought I'd field the question to see if anyone had come across something else that would be causing a similar noise. That's not to say that my daily 'not-so-gentle' driving isn't causing a problem of some sort.. :biggrin:
...
As Tavarish says "I am the warranty" lol
edit. Send a oil sample off to be analysed
Bahahahahaa... that's awesome! :thumbsup: And yes, sample collected and ready to go in the post.
Again, appreciate the discussion thanks everyone. Have a few things to poke at as soon as I get a chance, so either it's going to implode in the meantime, it's something else - which may be fine - or I'll find something when I get under the car next.
-- Adam
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