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Tps error code

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I replaced the tps. Cleared the warning light. Every thing was great during test drive: until I turned on the a/c.
Check eng light came back on and engine started performing eratic. Turned off a/c engine smoothed out but light stayed on.
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· Premium Member
6,101 Posts
Welcome to the forum. First off, what is the vehicle, two, how did you clear the codes, and three, remember the AC is tied into the idle when the AC is turned on to raise the rpm due to the AC draw.

· Registered
2 Posts
Discussion Starter · #3 ·
Sorry its a 1998 dodge Ram. Disconnected bat.ground.
Computer reader says high voltage tps.
Yes I know it is supose to raise rpm. But not cause eratic rpm and staling when you rev the engine.
Code and problem only happens after turning on the a/c. If you turn off ac the light stays on but engine runs fine. Its hot here and would really like to use the a/c.

· Super Moderator
1966 Crown Coupe, 2016 200 S AWD, 1962 Lark Daytona V8.
17,255 Posts
If both the A/C compressor and TPS are trying to squeeze through a bad engine-to-battery or to-body ground together, it may do just what you describe. The TPS signal voltage may be high because a bad ground is preventing it from a proper voltage drop.
Check and clean connections first.
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