I think you are on the right track. I would start logging the critical parameters and run through to find one that flatlines intermittently. You can definitely chase your tail for days until you find that one parameter. I've had an O2 circuit within the ECU die, dead voltage regulator within ECU, and a coolant sensor connector corrode before. All caused very mysterious symptoms until I happened to see the dead input in the data I was logging.

Corbin
'95 ESI-T

Now with more power and fewer leaks



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