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Worst case, bad ecu. Next, bad power transistor trio. Next, all coils bad (only if total no spark, not just no spark to some cylinders). Next, bad crank/camshaft positions sensors (fairly common). These are about the only no spark causes except a bad connection somewhere.


I'm inclined to agree with fasteddy. I had a similar situation on my 1989 3.0L SOHC 12 Valve engine once. Also on a highway situation, its kind of a funny coincidence now that I think about it. It turns out that I didn't plug in the connector to the power transistor all the way and it came loose. After trying to restart it on the side of the highway a couple times, I popped the hood and it took me about 5 minutes of looking at different things before I spotted the connector had come loose (had not completely come off, that's why I didn't notice immediately).

I reconnected it and it started right up.

The power transistor can be seen in this image. It isn't labeled but can clearly be seen just below and to the left of the ignition coil. Small black rectangular block with the connector attached to it.

[Linked Image]

89 Raider - V6, Automatic, rear LSD, A/C Retrofit, Cruise Control Retrofit.