P039C

Symptoms

• Check Engine light on
• Misfire in cylinder 1
• Unstable idle
• Loss of engine power
• Increased exhaust toxicity

Causes

• Low compression in cylinder 1
• Faulty or clogged fuel injector of cylinder 1
• Weak spark plug or faulty coil
• Cylinder pressure sensor malfunction
• Leaking valves or head gasket

How to Fix

1. Perform a compression test on cylinder 1 to assess the condition of the piston rings and valves
2. Check the spark plug and ignition coil of cylinder 1
3. Diagnose the fuel injector of cylinder 1 (balance, spray)
4. Check the pressure sensor and its circuit for serviceability
5. If necessary, perform a cylinder leak test.
6. Eliminate faults found and reset error codes

Related codes

Error P039C by Vehicle Brand