P0301

P0301

Diagnostic information - DME (DFI)

Misfire detection

NOTE:
- Poor fuel quality (low octane ratings/high ethanol content/high foreign matter content) can lead to reduced performance and increased fuel consumption.
- In extreme cases, this may also cause misfires.
- If a misfire has been detected, fuel injector diagnosis is deactivated until ignition off.
- Fuel injector diagnosis is active again when the engine is started once more.

Diagnostic conditions
- Engine temperature more than -20 °C (-4 °F)
- idle speed up to the red range on the tachometer
- No overrun condition
- No crankshaft sensor fault P0335, P0336, P0371 or P0373 detected

Possible fault cause
- Tank filled with poor fuel quality
- Tank filled with incorrect fuel quality
- Tank driven empty
- Water in tank
- Dynamic driving style when oil level is near minimum (oil foaming)
- Use of an engine-block heater
- Lines, power or ground supply faulty for electrical components listed below (loose contact, oxidation, etc.)
- Lines, power or ground supply faulty for DME (DFI) control unit (loose contact, oxidation, etc.)
- Spark plug(s) oiled due to oil entrainment in the cylinder
- Wrong spark plug(s) installed
- Mechanical or electrical fault in spark plug(s)
- Bar ignition module(s) faulty
- Power or ground supply faulty
- Fuel filter dirty/blocked
- Mechanical fault in predelivery fuel pump
- Mechanical fault in high-pressure fuel pump
- Mechanical or electrical fault in fuel injector(s)
- Oxygen sensor faulty
- Exhaust system faulty - flow severely restricted
- Muffler blocked / faulty
- Kink in exhaust pipe
- Catalytic converter damage
- Leak in intake-air distributor
- Foreign matter in intake-air distributor
- Fault in adjustment of intake camshaft timing (VarioCam)
- Exhaust camshaft timing incorrect
- Hydraulic tappet faulty
- Valve lift control faulty
- Valve seat or valve faulty
- Mechanical engine fault