My 1999 tahoe will not shift back up when I have the gas pedel to the floor. when i go to pass someone i put the pedel to the floor the trans. will shift down and the rpms go up and it just stays there it will not shift back up until i let up on the gas pedel then it will shift

Run fault codes and look for a TCM fault as it controls the shifting on the transmission.

it can also be your torque convertor clutch solenoid
or you 3 to 4 shift solenoid inside transmission

the cable adjustment from the engine to the trans its the one with a square section that goes on the engine side push the metal section in and pull back on the cable then push the gas pedal to the floor that should set it

1999 cavelier manual trans: My son was shifting his manual trans really rough (ramming through the gears to try to beat someone out at a light) and ended up not being able to put it into anything but 3 and 4 (straight up and down). We noticed that the shifter cable, that actuates the position of the arm on the transmission, had pulled away from a "c" clip and was not held into place about 8-10 inches down the cable away from the trans. The cable needs to be secured into that clip in order to let the wire inside move the trans. lever to shift. Otherwise you will be stuck on what ever "rail" your trans is on at the time of disconnection. It would be the first thing that I would check.

The vacume hose on the vacume modulater on the trans mission is nt hooked to full engine vacume or the engine isn't making vacume.The governer will make the trans shift to second anyway at redline but it's preety hard on an old car to redline it just to find out/ It's possible that youv'e got the shift detent cable that hooks to the carb set too tight or it's stuck as if it's floored. with the cable disconnected it should shift out al the way real early as long as thirs vacume on the modulater. Gas mileage freaks that drive around slowly unhook th shift cale so the trans shifts into high gear real early. Not much for passing and acceleration but they get a little bit better gas mileage.

If the trans.oil is dark brown in color and smell's burnt your tranny is probably on it's last leg.If tou have bad pump pressure or low oil you will have to rev the eng to get it to build enough pressure to move.Your detent cable or kick down cable is for passing,when you step on the gas when passing someone this cable is pulled causing the trans. to go into a lower gear and when you let off the gas it should shift back into a higher gear.if it's out of adjustment it will kickdown to soon or to late.If your car has alot of miles it may be in need of a filter and fluid change,but usually when slipping occures its to late and you will need a replacement tranny.Hope this was helpfull.

bleed the clutch or clutch disc worn

Sounds like a vacuum leak problem or maybe fuel pump/filter.

if u are getting a fault code saying it is the air flow sensor u need to replace it a reset the computer memory

the airflow sensor is between the throtle body and the the filter

once u have done that road test truck and check codes again

let me know how u went

ummm i would say you need to adjust your trans shift cable, check your fluid level, and the problem i had with my dodge was similar to yours... it was my 3rd-4th actuator spring, it had broke and couldnt hold the pressure to keep it in gear