VOLVO
ECM-321C - Misfire cylinder 1, three-way catalytic converter (TWC) damage. Catalytic converter damage
System
Engine Control Module (ECM)
Volvo models this fault code applies to
Applies to the following models:
2 modelsS80 (1999–2006), XC90 (2003–)
Show models by year and engine (2)
What does this fault code mean?
Misfires on cylinder one during starting can damage the catalytic converter. The code indicates cylinder one, and the fault should be corrected soon so the catalytic converter is not damaged.
Possible causes
- Blocked or leaking injector
- Uneven compression
- Air leakage
- Faulty fuel pressure
- Low fuel level
- Contaminated or incorrect fuel
What you can do
- 1First investigate the other fault codes that affect camshaft control or the camshaft reset valve
- 2Check the fuel level and that the engine oil level is correct
- 3Check the spark plug on cylinder one and the moisture in its well
- 4Check the intake system for leaks
- 5Check that the fuel suits the season and that the tank is not contaminated
- 6If the fault remains, have a workshop check the compression on cylinder one
Symptoms you may notice4
- Engine warning lamp lit
- The engine misfires
- The engine is difficult to start
- Uneven idle
What the fault can affect2
- Catalytic converter diagnosis is switched off
- Lambda control is switched off
General guidance for car owners. Diagnosis on the car can point to a different cause.