I have a 1997 F-150 4.2L in which i cannot get any spark to my coil pack.I have replaced the crank sensor,cam sensor and coil pack I still cannot get any spark.I did check all of the fuses(O.K.)and all of the mega fuses.I recieve no voltage to my crank sensor.This almost tells me that the pcm may be bad.The truck only has 119k miles no other problems ever with the truck other than basic maint.Any other suggestions.

 

...Welcome to Ford Truck Enthusiasts!

See you on the boards. ….

 

Probably not the PCM. Yours is not a typical PCM failure.

Have you run the PCM Quick-Test with a scanner to see what codes may be present?

Have you verified that the problem is indeed a "No Spark" condition and not due to lack of fuel or air?

Did you follow the diagnostic routines in the service manual to troubleshoot or are you just throwing parts and hoping to get lucky?

Does the CEL come on during bulb proveout (first several seconds after key is turned to RUN). What does the CEL do while cranking?

Check for power at the coil (R/LG) first (key in RUN). No power, check fuse F30 in the I/P panel.

Remove the 5 A fuse in the mini-panel and check for power at one of the terminals. If none, check under hood panel F24. Reinstall the fuse.

Have you tested the PCM POWER RELAY?

Lot's of things to check (in a logical order) before considering the PCM as a likely item.

Steve