I have an 03 w/ 3.8 and driving home on the freeway the other day I went to pass someone @ 70mph and when I got on it to pass it wouldnt kickdown and go, it just slowly accelerated and the rpms started to climb and the engine light started to flash and I let off it when the rpms got to 5500. I got closer to home and got off the freeway and under normal acceleration it would shift through all gears fine, took off from a red light and got on it a little and the damn thing wouldnt shift out of first and the rpms went up almost to 5500, got home hooked up my scanner and theres not one trans code or anything related. I can replicate this issue everytime, as soon as I get on it the damn thing will not upshift, fluids good and full, no codes etc. Any ideas?

 

Id make sure your not throwing a code, and sounds like a tranny problem

 

Like I said in the original post, its not throwing any codes

 

good luck then

 

You may want to bring a helper with you one time with the scanner hooked up to it, and see if a code sets while the engine light is flashing.

If you don't have any luck there, I would start by checking out the TPS