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What's a TPS?

2356 Views 3 Replies 3 Participants Last post by  qdub24
I've read the tranny sticky, and these symptoms describe the issues that I've been experiencing w/my tranny the last two days.

2. 1-2 shift does not happen at WOT until you let off the gas: Best case: try replacing the TPS. Middle case: leak in the 2nd gear apply circuit (servo assembly or 1-2 accumulator). Doublecheck by using the pressure gauge and watch for a big drop when the PCM commands 2nd gear. Worst case: poor line pressure rise (see below).
3. 1-2 Shift shudder at WOT; delayed or abnormal 1-2 shift; There's a problem ONLY on the 1-2 shift: 1-2 accumulator piston cracked or stuck cocked in the bore. Check the yellow spring inside the accum housing for breakage. Also, if the accumulator housing walls are scored, the housing must be replaced. Easy fix in the pan.
4. 1-2 shift is delayed and harsh, may not shift into OD: Check TPS for smooth and linear electrical response over the entire range of motion. If not, replace.

I've checked and refilled the tranny fluid, but that only helped slightly. So what is the TPS that may need to be replaced. A part number would be very helpful.
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Throttle position sensor.
Yup... I had a messed up TPS sensor (The voltage was never steady when it was plugged in w/ a scan tool) Anyway, I had all the same problems on that list.. It was a bear driving it 1300 miles like that but I had to.. Anyway, A new TPS fixed it up, it shifts great now..

Note. When installing the TPS, try to make sure its clocked right.. Push the sensor as foward (clockwise when looking at it from the passenger side) while snugging down the screws. You can get the idle TPS voltage down a little by installing it this way. Some say the TPS is not adjustable... I call that BS.. You can get a better, lower target TPS voltage when the sensor is clocked right
Well, I replaced the TPS today and it didn't make a bit of difference. I'm gonna take the car to my dad this upcoming weekend and leave it. I guess I'll be getting my trans rebuilt this christmas.
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