Installed the 1zz throttle body -

[tk-421]

I just found something out by chance: I can lower the revs when cold starting by pumping the clutch pedal. Every time I press/depress the pedal, the revs go down a notch. Don't ask me why.

[m911gt]

Originally Posted by tk-421

I just found something out by chance: I can lower the revs when cold starting by pumping the clutch pedal. Every time I press/depress the pedal, the revs go down a notch. Don't ask me why.

and stay down?

[mikenacarato]

Originally Posted by tk-421

I just found something out by chance: I can lower the revs when cold starting by pumping the clutch pedal. Every time I press/depress the pedal, the revs go down a notch. Don't ask me why.

ya i noticed that too a few days ago and i noticed it does that.


on a side note....still no cel after hard driving and a few weeks of time. the chip swap mod is a success.

[kustom play]

i swapped the chips and did some normal driving, im going to try to burp the coolant and drive it like crazy for a while to see

[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.

[MGargano]

Originally Posted by yarstar

Somehow the post got removed.

T-sport stated that you take your OEM TB, lay it next to the 1zz TB on the engine, unplug the 1zz and then plug the harness into the OEM TB, turn the car to 'on' but don't crank. Leave it for a few minutes, turn car off, re-plug the 1zz TB.

This, he says, will 'trick' the ECU to thinking the OEM have been reinstalled and fix the CEL. I haven't tried this yet, but it does sound smart.

Anyone have any success with this?

[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.