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TPS voltage jumping

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Old 06-21-2013, 12:37 PM
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Default TPS voltage jumping

Ok ive spent awhile tracking down this issue but still cant figure out why its doing it. I have a 98 camaro ls1 383 stroker 6speed. The car hesitates and stutters all the time, through the whole rpm range. At first I got a code for tps sensor voltage to high at wot. Ive tracked it down to the reference wire that supplies the 5v is jumping anywhere from 5v to 20v. At first I thought maybe the wire was shorting out so i reran a new wire from the pcm to the tps plug but still jumping. Do you guys think the pcm may be causing the bad voltage or possibly a bad ground messing things up. Thanks for any help.
Old 06-21-2013, 04:26 PM
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Also could a 5v reference from another sensor be messing up the signal back through the PCM.
Old 06-21-2013, 06:31 PM
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Check the TPS wires back in the harness, mine had a broken wire.
Old 06-21-2013, 10:55 PM
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I was sure that was the problem so I ran new wire from the PCM to the connector. I even thought it was good then after a few mins it started jumping again. I only redid the reference wire. I think I may do the signal and ground just to be sure. It's gotta be a wire somewhere. Or the computer is going bad.
Old 06-22-2013, 06:40 AM
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Put your scan tool on the car, turn the key ON do not start the car.

Put the scan tool where you can see it on the dash or windshield or have someone watch the voltage.

Do a wire "wiggle test", move the harness around slowly and watch tps voltage.
Old 06-22-2013, 08:34 AM
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I just tried wiggling the harness in several spots it would only would change the voltage a hundredth of a volt. With I think it was doing if I didn't touch it. I did notice though that my driver side o2 had 2 wires sliced. I didn't see it before. Ill fix that and see if it helps.
Old 06-22-2013, 12:12 PM
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Fixed the o2 wires and its still the same. It seems though the rough running doesn't start till its warmed up. If I check the voltage when its cold its always good. I can take it down the road when I get back and check the voltage is bouncing around all over the place.



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