when car is cold stalls and sputters at idle

[SHO--ripper]

when i start my car it sputters at idle and i have to give it throttle to keep her alive. when i give it throttle i have to keep pushing the pedal in and out to get the revs up. i replaced the tps already. any ideas what this could be? past 2000 RPM's no hesitation.

 

[BeatDaSHO]

try resetting the idle program. Do a search on it on the forum. SDPatt has a great one. If that doesn't work, then i would suggest you clean the IAB valve.

Greg

 

[SHO--ripper]

what is the IBA valve?

 

[shojuan]

Idle Air Bypass. It's the 4"X1.5" cylindrical shaped device on the engine side of the throttle body. There's a writeup of how to clean it on the shotimes.com website: Care and Feeding -> Engine Control.

I've had the same problem as you and have cleaned the IAB several times in my 89. You want to reset the computer afterwards. I just disconnect the battery, turn the car on and press the brake for 30 seconds. Reconnect battery, start and let the car idle by itself for a minute.

Also, maybe your CPS sensor is getting wet and going out. That seems to be my problem too and a new CPS is going in when I finish cleaning my garage so I can do my first 60K without the afternoon wind blowing dust everywhere.

Hope this helps.

Rick

 

[luigisho]

Could be any of those. When does the alternator take over from the battery around 1500rpm? just another thing to think about.

 

[SHO Mojo]

Dude...I had the same symptoms, and trust me on this: it gets MUCH worse in cold weather. My problem was indeed the Idle Air Bypass (IAB) control (also sometimes abbreviated as IAC, for idle air control). I replaced mine, but I understand removing and cleaning the unit often works, so try that first.

Good luck,