P034A

Crankshaft Position Sensor - Crankshaft Start Position Incorrect

High severity

At engine start the crankshaft position reported by the sensor does not match the calibrated start window — typically a wrong tone-wheel installation, sensor air gap, or PCM not synchronised after a relearn.

Common causes

Tone wheel misindexed or relearn pending
One of the most commonly reported causes for this code — check this first.
high
Typical part cost: $220-1650
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First things to check

1Confirm the code with a scan tool and check for additional related codes.
2Inspect the relevant sensors, wiring, and connectors for damage or corrosion.

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Related codes

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Frequently asked questions

What does P034A mean?

P034A means "Crankshaft Position Sensor - Crankshaft Start Position Incorrect". It is a generic OBD-II code that points to a fault in the ignition system or misfire.

What are the most common causes of P034A?

tone wheel misindexed or relearn pending — these are the most commonly reported causes. Verify with a proper diagnosis before replacing parts, or use the Wrenchify app for a vehicle-specific diagnosis.

Can I keep driving with this code?

This code points to a problem that can cause damage or affect safety. Avoid driving and have the vehicle diagnosed promptly. Use the Wrenchify app for a full diagnosis specific to your vehicle.

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