[Jackpine]

Well heck, I hate it when I can't be brilliant! :cry:

Again though, the failsafe mode is only "real" when the engine overheats. For some stupid reason then, I'd have to say it got a false "hot" signal from the CHT sensor. (This shuts down fuel injection and possibly spark on every other cylinder - but air is still brought in to cool things down).

Since the engine was clearly NOT hot, it had to be a false signal, and, I suppose it's possible for CHT sensors to fail suddenly, and maybe to the HOT status, but I'd think it unlikely. I'd also be surprised to see that code go away just because you reprogrammed the PCM to Level 0, if the sensor was bad.

I'll be most interested in learning what happens when you return the tune you had before. I am absolutely positive a tune cannot cause this failsafe symptom! (And if it turns out it can, I'll never give anyone advice again). :sniffle:

(I meant to add - If you continue to have trouble on the Level 2 tune, post your problem in the "Help - Emergency" forum. I think Bill would want to know about it right away! And, I suspect he monitors that forum pretty closely).

- Jack