no OD

[C-Power]

my tranny shifts hard into second then from second to third it shifts within 200 RPMs and again into 4th within another 200....i changed the Tps senser the shift sencers,rpm sencer, and the tranny computer but not the e-prom..any one got any suggestions????oh and all of a sudden the tail lights wont work??? and i changed the surcut bords.

[JD_countryboy]

what kinda vehicle you got? Is it your tail lights or brake lights that quit working?

[C-Power]

i got a 93' 1 ton 6.5 and all the tail lights went out except my licnece plate light..

[JD_countryboy]

Check all your fuses, every one. sounds like a short. trace your wires and make sure they are all ok and burned/rubbed thru. i know on my truck they were routed in a couple tight spots. Lose your tailights and have the tranny problem start at same time?

[JD_countryboy]

what do you mean no OD, 4th gear is overdrive. do you mean torque converter isnt locking up?

[C-Power]

im not sure i traced my ground wires and still nothin....i was told by a diesel workshop that it had 5 gears...but i dont know....it shows number for being a 4l80e...im not sure if its the torque converter because for a while i could shut the truck off and then restart it and it;d work for a while then it would stop workin again or i could unplug the transmission module then plug it back in and it'd work and now it just plain wont work...

[C-Power]

also if it was my toque then would that make it shift that hard??? from first to second???? adn then so quick from 3rd to i guess od??? ohhh it keeps pullin the code for the tps sencer.... but i show continuety through it

[JD_countryboy]

I don't have the gm service manual in front of me but i do know the tps has input to the computer for shift points. As far as testing the tps I'm unable to tell you that either.

[synthetic-oil]

If you don't have a scanner any DVM will do. It is also a go ideal to take the black wire and externally ground it. The negative from the battery is right there handy. I don't have my book in front of me but one of the other wires is 5 volts in. The other one is the one you want to hook your meter to and set the TP so it is 4.5 volts (or as close as you can get it) at WOT. I just had my tranny rebuilt and the screwed up more than they fixed so I have learned a lot. You need to check all the fuses, fusible links first. If after you do this and you still have problems you will need a scanner to go any further.

[C-Power]

well i have a qvc scanner so i got that covered....i checked the tps sencer and its set at 4 then 4.5 when open...what do you mean ground what wire externally???

[synthetic-oil]

well i have a qvc scanner so i got that covered....i checked the tps sencer and its set at 4 then 4.5 when open...what do you mean ground what wire externally???

You can get a connector that will fit over the black wire and then get a 16 gauge wire and insert into the conector and crimp it down. On the othe end of the wire crimp a ring connector on it and install it on the ground from the battery to the engine block.

What do you mean it is set at 4 and then 4.5 at WOT. It should be .80 volts give or take a few points at idel. If you are saying it is 4 volts at idel you have a problem.

[C-Power]

got er fixed....where my tps sencer was hookin up one of the prongs wasnt conectin so we made it thanks for all the help

[DetroitDan]

where is the tps located?

[C-Power]

mine is a 93 so i dont know if its the same but its right beside the fuel pump on mine....

[C-Power]

ok better decription it is inbetween the intake manifold and the top left of the injection pump if your lookin from the pront of the engine...its a little black circle with 3 wires runnin into it

[DetroitDan]

thanks c-power

[C-Power]

not a proplem let me know if you found it...if so then its pretty easy to change out just 2 bolts and set it

[DetroitDan]

I bought a TPS at Pepboys, but it doesn't fit my truck. Apparently 97 has some different kind of TPS on the pedal, they sold me one for an older truck, who knows why. I just changed the transmission input sensor and vehicle speed sensor with no change. I still have the same condition, real hard 1-2 shift and it drops out of lockup as soon as it gets warm. I am at wits end trying to fix this. So far I have changed the brake light switch, the engine coolant switch (thought it was trans temp at the time) checked the trans temp switch, working fine. I changed both shift solenoids, the torque converter clutch solenoid, and rebuilt the valve body with the Sonnax Sure Cure kit. Pan has been down and fluid changed about 6 times, filter a couple times. BTW, fluid has never been burnt or even dirty. I added some Lucas Oil trans fix, seemed to work for a couple days. That's the way it's been, everytime I try something it works for a couple days to a week so I think it's fixed, then it starts acting up again.

Tranny shop told me last spring that I need a tranny, but I'm sure I don't because I have all gears and lockup functioning some of the time. If it was mechanical it would stay broke. I am certain it is electrical.
Can anyone point me toward the grounds that I should check? Please help me, I'm begging you!!!!