*I thought I had a dead truck today- help!*
 

I have a lifted 2008 F150 4.6L, and I finally got around to changing the gear ratio (4.56) and tire size (2740) on my Evo today. I've been running it on Level 2, and decided to go back down to Level 1. When I turned the truck on, it seemed fine. I got to a stoplight to turn left, and when I pushed the gas to go, my truck lurched forward (mid-turn), and lost power. The yellow wrench then lit up on the dash.

I babied it into the grocery store parking lot, turned the truck off, and set it back to Stock settings. I then changed it back to Level 1 without changing the gear ratio or tire size, and it seems to drive fine now... what the heck happened?? Anybody else experience anything like this before?

:shrug:

No idea. But, it would possibly be helpful to know what code was thrown when you got the wrench light. If it happens again, check the diagnostics display for the "P-code(s)".

And, there's really nothing in changing Tire Size or Gear Ratio that should cause this, especially on Level 1. I'd also reload the Level 1 tune with those things changed and see what happens. (However, I think you get more benefit out of using the Level 2 tune.)

- Jack