Hi All.
I hope I can get some help here with my 88 fiero gt. Years ago I swapped a 99 park avenue 3800sc and the 4t65e-hd trans into it. It's been fine for the most part.
Over the fall I ran into a shifting issue. Out for a weekend drive and all of the sudden the trans was pretty much in 3rd gear only for forward gears. Reverse would also work. But no shifting at al. I have a regals gs obd2 pcm that was reprogrammed by sinister performance. It threw a CEL and the codes p0758 p0753 and p1860 showed up. I can clear the codes with the scanner and drive it for a bit and its fine. Then at random it'll go back into this Limp mode with these codes being thrown.
Seems crazy all of these solenoids and tcc would go bad all at once. Anyone ever had this issue come up in their 4t65e trans? I'd like to figure out where to start at to get it figured out. I am all ears. School me.
Thanks for the help. I appreciate it.