P0342 Camshaft Position Sensor A Circuit Low Input (Bank 1 or Single Sensor)

P0342 indicates a low input from camshaft position sensor A on bank 1 or a single-sensor setup. The cam signal is lower than expected or intermittently dropping out.

Code details

Generic OBD-II · P0

System: Ignition / Misfire
Code type: Generic (SAE / ISO controlled)
Standard: SAE J2012 / ISO 15031-6

Diagnostic boundary

A diagnostic trouble code reports that a monitored test failed. It does not prove one specific part is bad, and manufacturer logic can add vehicle-specific conditions.

Do not assume a no-start or misfire is ignition-related until the low cam signal and synchronization data are checked.

Symptoms of P0342

Rough idle, shaking, or a stumble under acceleration.
A flashing check-engine light during an active misfire.
Power loss and higher fuel consumption.

Common causes of P0342

Worn spark plugs, ignition coils, or plug wires.
Fuel-delivery problems — injectors, pressure, or a lean/rich mixture.
Vacuum leaks, low compression, or a mechanical fault in that cylinder.

Useful checks before replacing parts

Check cam sensor power, ground, signal circuit, connector terminal condition, and harness routing near heat or moving parts.
Compare cam signal with crank signal during cranking and running if scan data or scope testing is available.
Inspect sensor mounting, air gap where applicable, trigger wheel condition, and oil contamination at the connector.

Related OBD-II codes

These nearby ignition / misfire entries can help compare wording and pin down the fault area.