symptoms of a bad TPS sensor

Discussion in '1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-' started by 1995GTStang, Apr 25, 2009.

  1. What are they symptoms of a bad TPS sensor??

    My idle is rough.....well rougher than normal. I checked for vacuum leaks and found nothing. I have already replaced the IAC valve.

    The idle acts like I am running a huge cam. It has crane 1.7 roller rockers and some larger looking than stock springs.
    I am pretty sure that even if there was a cam installed it would not be this bad. What should the voltage be on the TPS and how is the best way to check??

  2. clean ur MAF, it might help a little bit... but if im not mistaken the tps should be around .98 i think... i could very well be wrong though
  3. Is the timing off? That could be causing the rough idle. My wiring was bad and my TPS sensor was not working at all and my car idled fine.

  4. IIRC the top wire is ground, middle is signal and bottom is VREF.

    Look for a clean sweep from baseline to WOT, with no breaks in the reading.
  5. I set the timing at 13 degrees after installing the gt40 intake. But the idle has been rough since I purchased the car.
    It idles like there is a very large cam in the car. It is not like its miss firing or pinging when I accelerate, if anything it is highly possible the car is OVER camm'd.

    I do not know much of the history of this car. I got a smoking deal on it (probably for the above reasons). It is just odd....I expected this idle to smooth out after installing the new intake. I fixed and replaced all the bad vacuum lines and anything that appeared to be frayed.

    What is the largest cam you can put into these with stock E7 heads?? It might just be the cam is counter productive.

  6. Basically anything bigger than a stock cam on stock E7s is counter productive.

  7. on what i hear that you dont have to adjust the tps voltage on sn95s unlike the foxes. clean the maf but also check the PIP sensor located inside the distributor.. just food for thought
  8. For the conversion guys, you don't have to adjust the TPS on a fox either. It either can baseline itself or it will set a code.