THIS WAS ORIGINALLY POSTED TO THE EXPLORER FORUM AND I HAVE HAD NO RESPONSE. ANY HELP IS APPRECIATED !!

I have a 1997 Ford Explorer 4.0 L V-6 with 211,000 miles. Motor was replaced approximately 12,000 miles ago and have had no problems until this weekend.
On a roadtrip, aren't problems always discovered on a "road-trip", the engine began misfiring climbing a moderate hill. At the bottom of the hill the engine died and would turn over but not restart. On investigating, I discovered the 25 amp ignition fuse was blown. Replaced the 25 amp fuse and the engine ran for less than 1 minute before blowing the fuse again. Replaced the fuse with a 30amp, the only other one I had with me, and managed to limp the vehicle the final 40 miles to my destinaton.

I then pulled the ingition coil and discoved it was cracked on the bottom with a solid white substance oozing out of the crack. I visited the local auto wrecking yard and purchased a used ignition coil and installed it on the vehicle. The vehicle started and ran fine and performed well on a short 20 minute test drive. The following morning, I drove the vehicle 15 miles and discovered that it ran smoother and appeared to have more power than it did previously. Approximately 15 miles into this drive, the engine once again started misfiring. Pulled the vehicle to the side of the road and with the engine ildling very roughly, checked under the hood. All appeared to be well when the engine died and a "puff" of blue smoked emitted from the front of the ignition coil.

Here's what has been done so far:

All grounds have been checked out and are good.
Replaced ignition coil with another used one
Routed additional ground from ignition coil to negative side of battery
Replaced negative battery cable.

These steps were taken and the ignition coiled installed. The vehicle drove for about 3 miles and fried the ignition coil again. The mechanic I have working on the vehicle, independent not Ford shop, advises the ECM may be bad. He his diagnosing that today but freely admits he is stumped as to what might be causing the ignition coil to blow.

Any ideas? Could the ECM be bad? I certainly do not want to drop $400 on a new ECM if that is not the problem.

Any assistance is GREATLY appreciated!

Glenn Siron
Yakima Washington


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<TABLE class=tborder id=post3622227 cellSpacing=1 cellPadding=4 width="100%" align=center border=0><TBODY><TR><TD class=thead> #2
04-24
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What is the voltage to the coil when the truck is running??
I presume he has checked for any stray grounds/shorts!
Is the intake manifold under the coilpack getting exceptionally hot?? Measure it..

 

Thanks Aqua. I will have him check those two areas. Yes. He has assured me he has checked all ground and checked the wiring harness for problems

 

Here's some info on this system.

http://www.autozone.com/servlet/UiBr...3d800b8e81.jsp

I would check the voltage B+ going to the coil like the other poster said, and I think I would then think about replacing the ICM, not the ECM. If I am reading the above info in the link correctly, the ICM is what drives the coils.