The computer code reader plugged into my '93 Silverado Pick Up is sending a TPS code.. My friend had no overdrive on his C3500 6.5 NA van, like me, and he changed the TPS, and got overdrive back... He also had a VERY hard 1-2 shift, a limp mode when the 'puter detects overheat condition, I was told.

My friend said he paid $85 at a Delco store. Here's double the price!

http://www.autopartsgiant.com/parts/?Ntt=throttle+position+sensor&=&N=0&uts=true

FLAP's get $110 and $140... HELP!!!

Oh yeah, this happened almost home from a 2700 mile trip to Iowa and back, towing a Corvair the last 800 miles. The truck has 281,000, and was working perfectly, with nice red oil

did you check the sticky at the top of the 4l80e section on no overdrive?

moved to 4l80e section

A scan tool will tell you what the tcm is seeing. I had a bad tcm that would loose the tps input and shift hard with no lock-up and no od. Everwhere I priced a tps they were well over $100. With a volt meter you can check if the tps is getting the 5 volt reference signal and if the ground is good.You can also backprobe the connector with the key on to check that the variable out put is working. There are 3 wires on the connector. Black is ground. One is 5 volts the other varies with throttle.
A scan tool will also tell if the engine rpm and input speed sensors are working

Thanks, sorry...

moved to 4l80e section