A little problem

[Jackpine]

That's more than weird! How can you have such bad performance and not see it on the tach?

Except, I wonder if the timing was suddenly wrong? Possibly overadvanced? You'd think there'd be "ping" though, if that were the case. And, if it was suddenly retarded, you'd certainly lose power, but I doubt you'd get the other symptoms. Valve timing? And, no codes - really weird.

Wonder what happens if you go back to the performance tune?

- Jack