wont idle with clutch in

[carbed 85 gt]

Alright this is on my 93 with trick flow HCI, I converted to 5spd and have the following problem. The car runs fine but when I am coming to a stop I have to keep a little throttle to kep it from stalling, it doesnt do it all the time. I have the stock EEC that is an auto and am not having any surging so I dont think this is an IAC problem. Any suggestions?

 

[GearHd6]

Does it idle fine just sitting in your driveway or does it idle low then also?

 

[5.0 Nostalgia]

Try cleaning the MAF sensor. This happened to me on my old 96 GT and that fixed the problem.

 

[TENGRAM]

Alright this is on my 93 with trick flow HCI, I converted to 5spd and have the following problem. The car runs fine but when I am coming to a stop I have to keep a little throttle to kep it from stalling, it doesnt do it all the time. I have the stock EEC that is an auto and am not having any surging so I dont think this is an IAC problem. Any suggestions?

the ECM relies on one sensor and one actuator to raise idle when coming to a stop to prevent the stalling that you are experiencing. the VSS tells the ECM the speed (that you're stopping), and the IAC gives the extra air to raise the idle. one (or both) of these is likely your problem.

 

[JChalfan]

the ECM relies on one sensor and one actuator to raise idle when coming to a stop to prevent the stalling that you are experiencing. the VSS tells the ECM the speed (that you're stopping), and the IAC gives the extra air to raise the idle. one (or both) of these is likely your problem.

I thought if your motor is warm, and your idle is set properly, you shouldn't need the IAC to keep the motor running when the clutch is pressed in. I have run 5.0's with the IAC disconnected and had no problems with them trying to die, except when they are cold.

I could be wrong, I just didn't think a faulty IAC would cause a warm motor to stall.

Jeff

 

[HISSIN50]

Tengram is right and Jeff noted a caveat. It's all in how the idle is set. I know guys who dont run a VSS so they set their idle a little on the high side (and set it with no IAC input, on a hot, unloaded motor) and they dont have issues.

If the IAC is needed for hot idle (due to how it was set) and the VSS and IAC interface that TG noted is compromised, then issues arise.

Good luck.

 

[jrichker]

See "Help me create the Surging Idle Checklist" at http://forums.stangnet.com/showthread.php?t=534062
for help with your idle problems. The first post contains all the updates to the fixes. I continue to update it as more people post fixes or ask questions.

 

[carbed 85 gt]

Alright, I have a good IAC on it its a new one (motorcraft) and I still have it from time to time. Most of the time the idle stays at @1100 until the car comes to a complete stop with the clutch in, but sometimes it just dumps the idle down to 500 or dies. I am going to try the VSS next. Thanks guys>:SNSign:

 

[GearHd6]

Yeah my idle hangs up about 1100 also until I come to a complete stop then it drop to about 750.