Another strange problem

[SteveVA]

I cleaned my MAF with q-tips and electical cleaner, It had a bit of gray/black dust, reassymbled and had idle problems. If the car is started cold, the idle is perfect, no sputter, no surge just a good solid 850 RPM idle. However, if the car is warm and I start the car, the idle will surge from 1500 down to 500 with each surge getting wider until it finally dies. I can feather the throttle and keep it running but if I let go it will die. This will continue until the check engine light comes on. Then the idle settles right down and will idle perfectly as long as I do not shut if off and restart it.

The OBD codes are 327 and 136. The 327 is because I do not have an EGR. To fix the 136, I have replaced the 02 sensors (didn't resolve the 136 code), checked the TPS voltage, replaced the IAC (replaced it before this issue began), performed the idle reset...multiple times, new plugs, new wires, new fuel filter (all replaced for mainteance purposes in the past couple of months).

Suggestions?

 

[hollywoodstang]

Checked your wires? mine did this and one or two of the wires were burnt. Didn't throw any codes tho

 

[94 Cobra 5.0]

i would suggest to disconnect the battery and wait about 5 minutes before hooking it back up. pcm has to relearn once you do this. might help might not but its worth a shot.

 

[SteveVA]

Thanks for the suggestions. I will recheck the wires looking for breaks or burns.

I did disconnect the battery and let it sit 30 minutes before reconnecting and starting the car. It did not change the behavior.