View Full Version : Auto not downshifting/ No burnout (LT1/4l60e)


4u 2 nv
08-06-2008, 08:40 PM
around town the trans up shifts just fine..breaks the tires loose very hard on the 1-2 with no problem...however..occasionally ill come to a stop and attemp to power brake the car. It wont even come close to spinning the tires over. Other times it will. Most of the time it wont though. Trans was rebuilt around 50K miles ago and has a tune, stock stall speed, servo and billit trans pan. Also if it could be the same thing. On the interstate there is no "5th" gear..obviously im referring to the convertor locking up. Could this be the lock up soliniod? i was told it also controls down shifting. Around town the trans seems to downshift properly. i can feel it go into first when rolling slow and whatnot.

Also if i powerbrake the car (and the tires wont spin) if i release the brake the car doesntly powerfully excelerate immediatly..it takes a few feet then wakes up...im about to set it on fire

Vince @ FLT
08-06-2008, 09:34 PM
Sounds like you have a driveability problem not a trans problem. I say this because it sounds like your car is loosing power when you load it up doing a brake torque. Also if you do not have lockup this could be caused my engine misfires, plugged exhaust, and so on. I would get this car into a shop to see what their thoughts are. Vince

4u 2 nv
08-06-2008, 09:40 PM
so a clogged cat/clogged fuel filter could keep the convertor from locking up? its the original cat on it and it has 160K miles. lol fuel filter doesnt look to new either.

Will an OBD1 scanner be able to pull the tranny codes to see if there are any? thanks for the reply vince

4u 2 nv
08-06-2008, 10:01 PM
also...from a 10MPH roll or so it will put the car sideways in first gear and attempt to in second. just when im at a dead stop..

Vince @ FLT
08-06-2008, 10:25 PM
so a clogged cat/clogged fuel filter could keep the convertor from locking up? its the original cat on it and it has 160K miles. lol fuel filter doesnt look to new either.

Will an OBD1 scanner be able to pull the tranny codes to see if there are any? thanks for the reply vince

If your computer is registering engine misfires it is possible. Just about any scan tool should work for you as far as pulling codes. I'm not familiar with all of them but most you can lie to about what year it is and at least get the codes.