Ok I put a 95 lt1 and 4l60e into a 1987 firebird and everything is great. I put a transgo shift kit in it and a custom made 3300 stall. I went to the track last night and the first couple of passes were fine then I made a pass and and when I was done I only had first gear. So I let the car and tranny cool down and everthing was fine? Then I made an other two passes and the same thing: only first gear after the pass, and the same thing let it cool and drove it home fine?

Could this be a sticky selonoid or could the heat be the problem, or could the heat be messing with the selonoids?????
I have a B&M 28000 GVW tranny cooler, But during the stagging there is no air flow, only from one of the fans.

It seems to happen after it is beat on in a race or when it gets hot.

ANY IDEAS???????
Thanks

 

I scanned the engine and tranny and the only thing I found was: TPS reading to high. Could this effect the tranny shifting????

 

Maybe. The 4l60e is computer controlled, meaning controlled by the sensors. Try replacing the tps.

 

The 4L60e is computer controled. There is no mechanical throttle valve. Without the proper computer or an aftermarket controler, you're not getting any line pressure rise with increased throttle. You're gunna toast it!

 

Your converter has to much slip in it. The computer sees the high amount of slip, thinks something is wrong, and puts the trans in limp home mode. Once you shut the car off, it resets. This can be compensated for by any good programmer.

 

More than likely what he said.

The early LT1 cars were notorious for this with higher stalls.

To a lesser extant the early LS1 cars were too.

Long story short the PCM sees too much slip and says "Go to hell" to you :-)

later
Jeremy