P020C

What it means

P020C is the generic code for a fault with cylinder 3 injection timing. The engine control unit has seen the injection timing (start or duration of injection) for cylinder 3 differ from what it commanded, or outside its allowed range. It is mainly seen on diesel and direct-injection engines, and how the timing is monitored depends on the model and engine.

Symptoms

• Engine management light on, possibly with reduced power (limp mode)
• Rough idle or misfire that seems to come from one cylinder
• Hard starting or extended cranking
• Diesel knock, excess smoke or a fuel smell from the exhaust
• Higher fuel consumption or poor acceleration

Possible causes

• Faulty or worn cylinder 3 fuel injector (sticking, leaking or slow to respond)likely
• Wiring or connector fault in the cylinder 3 injector circuit (high resistance, chafing, corrosion)likely
• Low or unstable fuel rail pressure from a weak pump, blocked filter or pressure control faultpossible
• Contaminated or poor quality fuel affecting injector operationpossible
• Crankshaft or camshaft position signal fault giving incorrect timing referencepossible
• Injector correction or calibration data not matched after injector or control unit replacementpossible
• Internal fault in the engine control unit or injector driverrare

How to diagnose

1. Read all stored and pending codes and the freeze frame data, noting engine speed, load, temperature and rail pressure when the code set
2. Check for related codes such as injector circuit, rail pressure, misfire or position sensor faults, and deal with those first
3. Visually inspect the cylinder 3 injector wiring and connector for damage, oil ingress, corrosion or poor pin tension
4. Check the fuel level, fuel condition and filter service history, and look for signs of contamination or water
5. Review live data for cylinder balance or injector correction values and compare cylinder 3 with the others
6. Measure fuel rail pressure against specification at idle and under load, following the manufacturer procedure for your engine
7. Check crankshaft and camshaft sensor signals and wiring for correct, stable readings
8. Test the cylinder 3 injector electrically and by the manufacturer's recommended method (for example leak-off or flow test), as the procedure depends on the engine

How to fix

• Repair or replace damaged wiring or connectors in the cylinder 3 injector circuit
• Replace the cylinder 3 injector if it fails testing, then code or adapt it to the control unit as the manufacturer requires
• Replace the fuel filter and correct any low-pressure or high-pressure fuel supply fault found
• Drain and replace contaminated fuel and clean the system as needed
• Replace a faulty crankshaft or camshaft sensor, or correct its wiring
• Update or reload the control unit software or calibration only where an outdated or faulty calibration is a confirmed cause

Can I keep driving?

Nearby codes

• P020BGenericCylinder 2 Injection Timing
• P020DGenericCylinder 4 Injection Timing