Installed the 1zz throttle body -

[AlexNet0]

maybe I just didnt use enough gasket maker, err, practice makes perfect I guess, lol, since someone mentioned that a leak can cause it to go nuts too.

makes sense now, because it did go nuts on me, lol

[mikenacarato]

i didnt use any gasket maker.

[AlexNet0]

hmm, guess Ill just try it and find out then, haha

[jkuchta]

I used gasket maker, and everything is fine.


The coolant has nothing to do with the rpm ocillations or CEL's, and besides, the way the lines are run there is almost no way for air to be trapped in the TB.

[tk-421]

I think I may have a problem.

It looks like the idle screw hole (where the allen wrench goes) is very worn, and now I can't seem to be able to adjust it! Anybody have a nice trick to fix this?

BTW the one-bigger wrench doesn't fit.

[yarstar]

I could never get mine to turn. I got all the epoxy off but still couldn't turn the screw. Eventually, I stripped it. I gave up thinking I could adjust the idle down anyway. Did anyone else on here ever get their idle screw turning and adjust down the cold idle?

[jkuchta]

I adjusted the scew, but it won't help the high cold idle.

Thats caused by the car running on a preset warmup map with a predetermined throttle setting, which is not adjustable in real time by the ECU. Until the car is warmed up, the ECU is in Closed loop (I think thats the one), which means the ECU is not responding to rpm or throttle position or O2.

One way to get that screw loose would be to hit it with a small torch for a few seconds to burn off the epoxy. Hold the TB with a few damp rags to keep from burning yourself or overheating the TB itself.

Someone also suggested that you can freeze off the epoxy.

[m911gt]

i removed the epoxy with a dental pick and a little patience. i just kept picking away at it and used compressed air to blow the debris away...but turning it doesn't adjust the idle at all ? ?

one way you could still adjust the screw if it is stripped would be to put super glue on the end of the allen key and actually super glue it into the screw. i know it sounds kind of stupid, but it should work. after you have adjusted the screw/idle to your liking (if it will adjust anything), just use a bit of extra force and free the glued key.

[severous01]

dont know if it's been mentioned but here ya go...for OBD2 cars any way

when u replace the IAC motor or throttle body you MUST re-learn the iac.

here's how:
1 remove batt neg and hit brakes, turn on lights, and do whatever you think you can to drain capacitive discharge

2 reconnect battery

3 start car

4 wait 10 minutes

5 shut car off

6 wait till cool

7 start over from 3 n go to 5

you should be fine after that.



also, you may have what's called 'tip in hesitation' with a larger than needed throttle. it's when there's more air getting to the cylinders than what's needed. is it bad? eh...i dont like hesitation in my throttle and would rather smooth bore the stocker, maybe polish it. on my camaro i installed a 58mm dual bore throttle. all i had for performance was exhaust (did with TB) and intake...so when i hit the throttle it would pause for about a half a second then seriously kick u in the seat...any way. put the stocker on and it pulled just as hard with no hesitation...

take it for what you will, but if you're getting hesitation ur getting too much air. get bigger injectors or more power n you'll need the throttle.

[severous01]

also, another good 'free mod' would be to bypass the coolant in the throttle body.

nets about 5hp in a v8 camaro, and about 4 in a v6. if you're doing a cai and all this stuff....why you gonna heat up that cold air to about 215*????

any way, just pull the coolant inlets and get a vacuum hose connector or some nickel plated pipe with hose connectors. butt teh two coolant l ines together and dont worry about the TB temps any more...

oh, by the way, if you live in a really cold area dont do this mod. the coolant heats up the air temp and allows smoother running engine for cold weather.

[m911gt]

I'm about to post up my 1zz tb for sale. If anyone's interested, please PM me. I cleaned the valve and cylinder and drilled the rivets out so the 1zz tb + 1zz chip + all hardware will be $65 shipped in the US.

[AlainMikli]

I wonder how the stock(1nz) intake tube can bolt onto 1zz TB since the 1zz has bigger outer diameter.

[tk-421]

Originally Posted by AlainMikli

I wonder how the stock(1nz) intake tube can bolt onto 1zz TB since the 1zz has bigger outer diameter.

It can, but you need to increase the inner tube diameter a little. I used a dremel with a filing bit and it came out great.

[tk-421]

I did the chip swap by keeping the OEM chip and ditching the 1ZZ chip. Took 5 minutes to remove the rivets using a drill with a small bit and another 5 minutes to screw everything back up. Have yet to encounter a CEL due to this.

[white_rice]

Originally Posted by tk-421

I did the chip swap by keeping the OEM chip and ditching the 1ZZ chip. Took 5 minutes to remove the rivets using a drill with a small bit and another 5 minutes to screw everything back up. Have yet to encounter a CEL due to this.

Thank you. So you just swapped the chip, but didn't touch that idle screw at all?

[white_rice]

Originally Posted by tk-421

I did the chip swap by keeping the OEM chip and ditching the 1ZZ chip. Took 5 minutes to remove the rivets using a drill with a small bit and another 5 minutes to screw everything back up. Have yet to encounter a CEL due to this.

Also what size screws did you use to replace the existing rivets?

[tk-421]

Originally Posted by white_rice

Too many variables here. Suppose I will start with the chip swap and move along from there.

The chip swap should be enough to fix it. I'm 99% sure the idle screw just helps nudge the idle up or down in the RPM range, but not enough to throw a CEL.
Just make sure the battery has been disconnected for a while. Otherwise you won't be able to tell for sure if it's due to the ECU storing previous settings or not.

Originally Posted by white_rice

Also what size screws did you use to replace the existing rivets?

Dang it! I knew you were gonna ask that...
Unfortunately I can't tell for sure. I just looked around for some screws and I found the perfect set with nuts to match.

[Rigaud]

I did not disconnect the battery, left it live. Swapped chips and removed the epoxy to dial the idle but only while it wasn't running. The P0505 is due to high idle and the oscillation the ECU searching and needs to learn. I had the oscillation too at first, it went away after a day or two. I had the P0505 popping up every day for two weeks but it took longer every time for it to show up. Eventually all has settled itself and works great. Best direct upgrade I did so far. My installation went fairly well because I did some reading on hear first before doing the job and not after the fact. ;)

Give it some time for your ECU to relearn with the bigger TB.