An engine light (a shape of a wrench) came on today while I was driving and my truck began vibrating and shaking upon acceleration and overall felt weird driving. Looked at the manual and the symbol of the wrench meant something was wrong with the Electronic Throttle Control. I took it to my mechanic and he said I need to get my PCM reflashed since my truck is an '04. I have a gryphon programmer so should I set it to stock before I get the PCM reflashed or does it matter? Thanks

 

Woah!! You don't need a reflash just yet. You need to use the Gryphon diagnostics and find out for sure what caused the wrench light. The PCM does not do that unless something caused it, such as bad COP, bad plug, throttle bodt, etc.

If you do take it to the dealer for any reason, set it back to stock prior to going, and if you have custom tunes, do not let them reflash as it will make your custom tunes worthless.

 

I had similar problem. my codes were related to throttle body and throttle position sensor. Truck was going into "limp home mode". Took off throttle body and cleaned it (easy job to do), problem went away. I was told otherwise it needed throttle body and throttle position sensor. But definitely check the codes before going to dealer.

 

Yeah, my truck is going into "limp home mode" too. He said the '04s need the PCMs flashed to update the computer. I dont have any custom tunes so I dont have to worry about those going away.

 

If you are going into limp mode, I have never heard of a reflash to fix it. That makes no sense at all. Find out what your code s are, what the is causing the problem.