Weird Idle problem...

[Tall]

Well; here is the problem. I have a slight miss at Idle. It runs great with my foot on the gas; and when its cold. Only when its warm and drops down to its lowest idle do I have a problem. It is also intermittent; sometimes two cylinders will misfire; sometimes one; and at no time interval.

The engine is rebuilt at a very good quality shop; and the TBI is rebuilt (new regulator, injectors, cleaned, and gaskets) all the sensors but the Temp; TPS, and EGR are replaced.

I can find no vacuum leaks; I put new plugs and wires and O2 Sensor (Accel Premium stock or something) and A/C Delco. I just bought a new performance distributor yesterday; and reset the idle. It still does it.

Now here is my question.

When I was breaking in the cam (not sure if it needed; but I figured better to be safe than sorry) I left the timing bypassed…because I didn’t want to turn off the truck and risk losing a lobe. Well after 15mins I noticed my headers where…kinda…glowing red =X (needless to say it was very cool to see.)

Could I have killed my 02 Sensor and spark plugs when that happened? The truck ran as smooth as glass on the first day. And seems to be getting a bit worse as time progresses.. It now will sometimes stumble twice in a row instead of just once. But the second I tap the gas pedal…all my problems are gone.


Thanks for your help!

God Bless;

Josh

[Tall]

Clarrifying a bit:

actually I replaced an EGR valve with a GM one (from factory) last year; but the EGR Solinoid is original; and the so is the knock sensor.

[2000CAYukon]

It could not hurt to check the plugs. I would also pull the 02 and take a look at it.

Was the dist rebuilt or replaced? Did you have the miss before the engine was rebuilt? I fixed a miss on my 90 K1500 by cleaning the connector of the pickup coil at the ignition module. The screens at the bottom of the dist where clogged and the extra heat and moisture in the dist cause the terminals to corrode. A little emory cloth and then some dielectric grease and she is running good now.

The pickup coil and upper shaft bushing is a common problem area on our trucks.

Do you ever drive to San Jose? I have a cable and WinALDL which can help diagnose the problem.

//2000CAYukon