5 PCM (computers) gone out in 6 mths

[deb468]

ok...someone, please, please help me!!! i have a 97 eddie bauer expedition that is driving me crazy. my husband is a mechanic and used to work at ford, but neither him or any of the ford mechanics or any other mechanic he knows has been able to figure this out. last august the original pcm went out. i was driving down the street and the engine died. he replaced that one, then 2 wks later it went out. the 3rd one he put in lasted until 3 wks ago. it went out and the 2 more in the past 2 wks have gone out. all O2 sensors have been replaced and all ground wires have been checked as well as all electrical connections. something is spiking the pcm and the memory is wiped out. can someone please give me an idea as to why this keeps happening.

 

[JimsZ]

Is it possible that your windshield is leaking water and it's dripping down into the pcm ? I had heard this was a problem with Expeditions while researching before I bought mine. Drivers side windshield leaks water down A pillar and right into pcm. Is this happening when/after it rains each time?

 

[Chesterfoxes]

You should think about providing a separate and new power supply from the fuseblock directly to the PCM. Route the new power supply through a relay that is activated by a connection from the old PCM power supply.

Paul

 

[green03]

Is it possible you have a bad plug wire (non COP) that could be arcing to a sensor wire and frying the PCM?