Hello,
My first time posting so here it goes.....After doing a valve job on a 3.2 motor I failed to notice that the spark plug's electrode on cylinder number four was bent and upon startup, the coil pack to that cylinder arced and melted. After resolving the spark plug problem with new plugs, I started it back up and now have a dead number four cylinder after checking all three components (air, fuel and coil). I have good compression (150psi in all) and have ruled out that it is the coil (swap with other cylinders) or injector (same swap). My question is....could there have been a spike back to the ECM, PCM to kill the signal it is supposed to send to cylinder number four? I have no way of checking the ECM other than swapping it with another one (expensive). Any help??? Thoughts???

 

Just to clarify on my post.....the spark plug electrode to ground was closed which caused the arc. Could this have damaged the driver for the # 4 spark in the ECM?

 

use an old style test light and see if u have the ground pulse for the coil driver with it unplugged.

 

ok, old style test light. like the kind you connect to the battery negative and then insert the "probe" end into the harness? I did that already and it shows power while running.

 

was not asking for power I was asking for the ground pulse from the pcm.

Connect the lead to the + side of the battery when the car is running unplug the coil and test for the ground it will be flashing quickly.