TPS Question
Thread Starter
Instructor
Joined: Oct 2002
Posts: 126
Likes: 0
From: STERLING Va
TPS Question
I am having a problem with my 86, It wants to buck or surge between 800-1100 Rpms. I have already done the Cap, plugs wires, rotor. but It still does it, I found a Vacuum Leak and fixed that and it helped but did not solve the problem.
I am thinking it may be a faulty TPS (Throttle Position Sensor)? Any thoughts if that may be the problem??
I also have a Air/Fuel Gauge and when you down shift it shows that the engine is beyond lean, when I get within the 1100Rpm(problem range) of down shifting it goes back up to idle(stoch.)
This leads me to believe that the TPS is thinking it needs to idle when it still has some Rpm to go.
If you don’t think that this is the problem or you have any idea what the problem may be please let me know.
Thanks for your thoughts and help in Advance!
I am thinking it may be a faulty TPS (Throttle Position Sensor)? Any thoughts if that may be the problem??
I also have a Air/Fuel Gauge and when you down shift it shows that the engine is beyond lean, when I get within the 1100Rpm(problem range) of down shifting it goes back up to idle(stoch.)
This leads me to believe that the TPS is thinking it needs to idle when it still has some Rpm to go.
If you don’t think that this is the problem or you have any idea what the problem may be please let me know.
Thanks for your thoughts and help in Advance!
Team Owner
Joined: Mar 2000
Posts: 83,381
Likes: 87
From: Boston, MA
Grab a mulitmeter and a couple of pins. Jam the pins through the top and middle wires on the TPS harness and put the multimeter into voltage mode. At idle you should get a value between 0.54v and 0.68v. Have someone watch the multimeter and turn the key to just on. Slowly press the gas pedal and the meter should show the volts rising steady towards 5 volts.
0.54v @ idle position is the factory stock setting.
0.54v @ idle position is the factory stock setting.
Burning Brakes
Joined: Oct 2002
Posts: 835
Likes: 3
From: Water Winter Wonderland
Re: TPS Question (CLUTCH^Master)
I also have a Air/Fuel Gauge and when you down shift it shows that the engine is beyond lean, when I get within the 1100Rpm(problem range) of down shifting it goes back up to idle(stoch.)
You can get a nice little adapter from MAD or TPiS that can be used with a voltmeter to check and/or adjust your TPS. Better yet, get a scanner.
Good luck finding/fixing.
