My truck acted up the other day and everything points towards bad COPs. However, I have replaced the Accel ones one the driver's bank with Motorcraft that I had taken off but were still good when I put on the Accel ones and now, today, I picked up a brand new test one from AutoZone. Nothing is reviving the 3 dead cylinders on the driver's side. I just replaced the front COP and started the engine - I unplugged the COP and it made no difference at all. The codes are P0354, P0355, P0356, and P0358 which show ignition coil D, E, F, and H respectively. I guess I need to see if there is power coming into the COP next, but does anyone know if there is a relay or something that might have hit that many cylinders at once? Any other fail-safe that would cause them not to fire?

 

Had a friend with some good knowledge and better diagnostic tools come by today. It looks like it is the computer. The coils have power but no ground and the ground - in this case - is apparently the computer itself. We have one more test to do Monday - but it seems as though I will need a new computer.

 

Have to pick up a computer today. Turns out the the 4 wires feeding the 4 cops that are not working are all on the bottom side of the computer pin connector and all lined up in a row. I didn't get it pulled apart, but it is clearly the computer. Might be something to remember when a "bank" of COPS fail.