Check Engine Light Code P0340 | O'Reilly Auto Parts

Diagnostic trouble code P0340 refers to “Camshaft Position Sensor Circuit A”. If you’re experiencing this code on your vehicle, it often points to fault in the camshaft position sensor or wiring, which can cause issues with performance, efficiency, and overall engine operation. You may also experience your engine dying and failing to restart, hard starting or extended start times, misfires, or a rough engine idle or poor acceleration.

Issues related to a P0340 code can often include:

Camshaft position sensor
Misfiring/rough running engine
Control module
Loose circuit connections
Damaged/corroded wiring harness or connectors

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OBD-II fault code P0340 means “Camshaft Position Sensor Circuit A”, and typically appears when the circuit wiring of the camshaft sensor is faulty in some way. You could see multiple other error codes associated with this problem, and if it goes unresolved, it can cause major issues with your vehicle’s engine performance, even leading to engine damage.

P0340 Code Diagnosis

When you experience a P0340 diagnostic trouble code, your vehicle may be experiencing failure in one of a few areas:

Camshaft position sensor
Misfiring/rough running engine
Control module
Loose circuit connections
Damaged/corroded wiring harness or connectors

Aside from a Check Engine light, symptoms of a P0340 Code can include:

Check Engine light
Hard starts or cranking without starting
Engine hesitation/stalling
Dying and not restarting
Misfires
Rough running
Poor acceleration

Whether you notice any symptoms or not, it is not recommended that you drive a vehicle with this code until the problem is diagnosed

Risks of Driving with a P0340 Code

Your vehicle may still run, but driving has the potential to make the problem worse or cause damage to other systems.

What does DTC mean?

DTCs, or Diagnostic Trouble Codes, are generated by data collected by your vehicle’s onboard diagnostics system, or OBD system, and trigger your Check Engine light by identifying problems with one or more of your vehicle systems. DTC codes help explain what the issue is and where it is located.

Learn more about DTC codes

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What are the most common DTCs?

Some of the most common DTCs include:

P0300-Random or Multiple Cylinder Misfire Code
P0301 through P0308- Single-Cylinder Misfire Codes
P0446- Evaporative Emissions Control System Codes
P0455- Evaporative Emissions Control System Codes-Leaks
P0420 or P0430- Catalyst Efficiency Codes
P0141- Oxygen (O2) Sensor Codes
P0171 or P0174- Lean Code
C0221- Wheel Speed Sensor

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Can I clear DTCs?

To clear DTCs, you can use an OBD-II code reader to scan and clear the codes. However, this will only temporarily turn off your Check Engine light. If the problem is bigger than a code or sensor reset, the Check Engine light will likely reactivate.

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