no signal from PCM to 1 and 4 coil in the coil pack. Other cylinders work fine. Dead cylinders still getting fuel. New wires, plugs and coil pack, no codes have been generated except the generic 0300 multiple misfire. If I connect an LED test light to the wires that run from the PCM to the coil pack, all are but the 1/4 cylinders are receiving a signal. Is this a symptom of a bad PCM, or is there something else that would cause just 2 cylinders to quit?

 

seems to be somewhat heat related, I can sort of control the spark by heating or cooling the area near the upper connector on the PCM which contains the wires from the coil connector. When the cylinders aren't firing, I have tapped the computer and the idle will smooth out.

 

new connectors?

 

what year mini van is this? and 3.8 3.3 or 2.4?

 

3.8L engine. Also, if I tap a bit harder on the computer that fixes the idle, sometimes I can get the engine to quit. Also, Cylinders 1 and 4 condition is either no spark at all, very weak spark, or full spark. The other cylinders are full spark all the time. The wire emerging from the PCM to the 1/4 coil is where I am getting this fluctuating spark condition using an LED test light.

 

sounds like a bad pcm then.