What causes TPS high voltage?

Usually a failed TPS or an open ground wire that pulls the signal high. Less commonly a short in the wiring.

Does P0123 cause high idle?

Yes — the ECM thinks the throttle is partly open and may raise idle speed or behave erratically.

High Severity

Fuel System

TPS voltage is above maximum expected. ECM sees the throttle as more open than it actually is.

Common Fix

Replace TPS

Estimated Cost (DIY)

$20 - $100

Failed TPSlikely

Open ground wirepossible

Short to voltage in signal wirepossible

Need to read or clear this code?

What causes TPS high voltage?: Usually a failed TPS or an open ground wire that pulls the signal high. Less commonly a short in the wiring.
Does P0123 cause high idle?: Yes — the ECM thinks the throttle is partly open and may raise idle speed or behave erratically.

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