TPS cannot get high enough voltage
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Joined: May 2002
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From: Vinemont Al
TPS cannot get high enough voltage
A week or so ago I decided I would gunk and wash engine. Drove it a little and started acting up and shut off in my driveway. Probably got water in TPS. Checked the voltage on TPS following procedure on here. Had only .27 or .28 volts. Replaced TPS and still could only get about same voltage. Never was able to get .54 volts. Yes, I adjusted idle air like in instruction before TPS.
It did crank and run the next day after got it wet and showed a code 36. I cleared it before I put the new sensor on. Haven't rechecked the codes but it isn't showing check engine light.
i am driving the car now and seems to be running OK but does seem like it could idle little better.
Done a lot of reading and haven't found answer so come here to ask.
It did crank and run the next day after got it wet and showed a code 36. I cleared it before I put the new sensor on. Haven't rechecked the codes but it isn't showing check engine light.
i am driving the car now and seems to be running OK but does seem like it could idle little better.
Done a lot of reading and haven't found answer so come here to ask.
Le Mans Master
Joined: Sep 2013
Posts: 6,192
Likes: 750
From: near the thumb in the mitten
If you didn't use scanner to set tps I would try to get it scanned and set. Verify you have 5v at sensor connector. The 36 relates to MAF burn off could have been set by cleaning engine.
Racer
Joined: Apr 2018
Posts: 349
Likes: 55
A week or so ago I decided I would gunk and wash engine. Drove it a little and started acting up and shut off in my driveway. Probably got water in TPS. Checked the voltage on TPS following procedure on here. Had only .27 or .28 volts. Replaced TPS and still could only get about same voltage. Never was able to get .54 volts. Yes, I adjusted idle air like in instruction before TPS.
It did crank and run the next day after got it wet and showed a code 36. I cleared it before I put the new sensor on. Haven't rechecked the codes but it isn't showing check engine light.
i am driving the car now and seems to be running OK but does seem like it could idle little better.
Done a lot of reading and haven't found answer so come here to ask.
It did crank and run the next day after got it wet and showed a code 36. I cleared it before I put the new sensor on. Haven't rechecked the codes but it isn't showing check engine light.
i am driving the car now and seems to be running OK but does seem like it could idle little better.
Done a lot of reading and haven't found answer so come here to ask.
Thread Starter
Advanced
Joined: May 2002
Posts: 65
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From: Vinemont Al
I'm stumped!
Still only .28 volts on TPS voltage check setting it high as it will go. The TPS sensor is new. Gives same voltage as old one. Also just changed the ECM. No change. Checking the voltage to the TPS plug I got 5.0 volts. Not a electronics guy by any means. Had this car nearly 18 years. Never was not able to get .54 on TPS setting. I'm wondering if TPS is still bad? You can extend it by pushing lever down after its reached it max in the slots and voltage will go up.
Racer
Joined: Apr 2018
Posts: 349
Likes: 55
Still only .28 volts on TPS voltage check setting it high as it will go. The TPS sensor is new. Gives same voltage as old one. Also just changed the ECM. No change. Checking the voltage to the TPS plug I got 5.0 volts. Not a electronics guy by any means. Had this car nearly 18 years. Never was not able to get .54 on TPS setting. I'm wondering if TPS is still bad? You can extend it by pushing lever down after its reached it max in the slots and voltage will go up.
An easy way to verify if its the wiring or the TPS would be to take the TPS off the car, and 'bench test' it. With the TPS unplugged, take an Ohmmeter and measure from the signal port (middle I think) to ground. Open the TPS slowly, and observe resistance readings. Does the resistance go up evenly? Or does it jump around, stay still, go out of range?
The next test (which I think you've essentially done already) would be to put the TPS back on the car, plug it in, then measure voltage from signal to ground as you open the TPS slowly. Again, it should increase smoothly, and not jump around or stay still.
If the first test fails, then the TPS is likely toast. If it passes and the second fails, then I would suspect a bad ground or connection, possibly at the ECM, but possibly anywhere in the wiring harness.
Burning Brakes
Joined: Dec 1999
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From: Columbia MD
Thread Starter
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Joined: May 2002
Posts: 65
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From: Vinemont Al
Tps
I really appreciate the help. Like I said I replaced ECM, TPS. Still only get .28 volts on it after unplugging IAC and setting rpm at 450. I also took an old Tps sensor and reinstalled it on my car. It to would only go .28 volts. Was only getting .28 volts the reason i put new tps to start with. Cars runs but idles kinda rough and still throws code 36. I have swapped burnoff relays, tighten and loosed ground wire under booster and one under ac on the frame.I've cleaned MAF sensor.
i have a box full of maf, tps sensors, burnoff relays I have changed on this car in 18 years. Really been an ongoing problem. I'm thinking maybe the IAC may be a problem or bad maf. I really hate to be a parts changer like most shops do but I am stumped on this one. I've never not been able to get .45 volts on tps in those years but I caint.
I will take the sensor off and see if I have steady resistance when I have time. I'm not going to trust this car till I get this fixed and no codes glaring at me. Maybe I just need to trade up a few decades. Hope newer vetted don't have this problem. I've read a lot and code 36 is one of the biggest problems with these years. Seems everyone has found their culprit and all are different reasons. Wish I could find this one.
tps
i have a box full of maf, tps sensors, burnoff relays I have changed on this car in 18 years. Really been an ongoing problem. I'm thinking maybe the IAC may be a problem or bad maf. I really hate to be a parts changer like most shops do but I am stumped on this one. I've never not been able to get .45 volts on tps in those years but I caint.
I will take the sensor off and see if I have steady resistance when I have time. I'm not going to trust this car till I get this fixed and no codes glaring at me. Maybe I just need to trade up a few decades. Hope newer vetted don't have this problem. I've read a lot and code 36 is one of the biggest problems with these years. Seems everyone has found their culprit and all are different reasons. Wish I could find this one.
Sorry for the late reply. So to clarify: if you take the TPS, while plugged in, but off the throttle body, it won't go above .28 volts when wide open? That would indicate either a bad TPS, or a bad ground/connection in the TPS circuit. When I did my MAP conversion, I wired the MAP backwards (I swapped +5 and ground) and that made the TPS read a consistent .4 volts until it was halfway open, then it would jump around. I fixed the MAP connection, and all was good.
An easy way to verify if its the wiring or the TPS would be to take the TPS off the car, and 'bench test' it. With the TPS unplugged, take an Ohmmeter and measure from the signal port (middle I think) to ground. Open the TPS slowly, and observe resistance readings. Does the resistance go up evenly? Or does it jump around, stay still, go out of range?
The next test (which I think you've essentially done already) would be to put the TPS back on the car, plug it in, then measure voltage from signal to ground as you open the TPS slowly. Again, it should increase smoothly, and not jump around or stay still.
If the first test fails, then the TPS is likely toast. If it passes and the second fails, then I would suspect a bad ground or connection, possibly at the ECM, but possibly anywhere in the wiring harness.
An easy way to verify if its the wiring or the TPS would be to take the TPS off the car, and 'bench test' it. With the TPS unplugged, take an Ohmmeter and measure from the signal port (middle I think) to ground. Open the TPS slowly, and observe resistance readings. Does the resistance go up evenly? Or does it jump around, stay still, go out of range?
The next test (which I think you've essentially done already) would be to put the TPS back on the car, plug it in, then measure voltage from signal to ground as you open the TPS slowly. Again, it should increase smoothly, and not jump around or stay still.
If the first test fails, then the TPS is likely toast. If it passes and the second fails, then I would suspect a bad ground or connection, possibly at the ECM, but possibly anywhere in the wiring harness.
Last edited by revets00; May 27, 2018 at 10:17 PM. Reason: Mistake
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