hey i now jumpy idle when warm is iac and cold is fitv. but i fixed it and now my idle is at 150 rpm's thats crazy low. it drives fine. idle screw dosnt work for some reason? went both ways all the way. now back to original position. question was this is a warm issue only so could my iac be the problem. not jumpy jus real low idle which isnt found in search. thanks alot in advance.

 

150rpm is way too low. you tac has to be off, because i cant get my car to run below about 350rpm. i know when my car was idleing really low it was because my tps was unpluged so it was throwing a code and idleing like it was about to die. is your cars cel on?

 

Start with a throttle body cleaning and battery disconnect, let us know please, you dont have security system or need a radio code to reset do you?

EDIT
What ever you unplugged, reseat those plugs and be sure they snap into place, maybe someting is not fully attached that you took apart.

 

wo!!! now im realy screwed. switched out my iac and started it up and a realy low rattle noise is cumming from the intake. i took the intake off to see if that was what made the noise but then it was cumming from the throttle body! its realy loud and basically sounds like a crapy muffler set up. i switched back to the other iac and does this still. one thing i found out was when i unplug the sensor on it it almost dies but the noise goes away. but no way both iacs are bad. any suggestions. i need my car for tomarrow have a special event. thank u much in advance

 

The IAC is making the noise, you proved it by disconnection it, Ford does the same thing, growl noise through the intake. The other one may be bad too, can you take it apart and clean it, I never took one apart.

It is possible that the ECU in not controlling it but lets hope its only an IAC.

 

ya well took everything apart that was throttle body and iac related. cleaned all, put it all back together and now the noise is gone so thats good news. but i still have crapy idle? at cold it idles at 900 rpms but as it warms it jus keeps dropping and dropping?

 

OK,now adjust the idle screw top corner of throttle body. Common screwdriver. Fully warmed up.

 

went both ways all the way and didnt adjust anything. when i turn A.C. on the idle drops so low the car starts to shake.

 

I believe the idle adjustment screw allows more air to the IAC so there may well be a computer control issue here, you may need to get it scanned (scan data) and see what the IAC is actually doing.

 

well see im running a jdm h22a with the same ecu that came stock with my h22a4 SH motor. so i know theres difference in compression. im in the process of getting obd2 to obd1 conversion harness and a p13 but the guys on here said theres not a whole lot of difference. i thought the ecu difference was killin me considering i still jus beat my buddys bone stock prelude base model same year by a hair. especially when i have full exhaust, headers, aem v2 intake, and skunk 2 manifold, plus a six puck clutch, and lsd. a hair? i should be alot quicker than a bone stock lude.

 

bump?