VW Lupo
The 1.4L MPI (44 kW) in the Lupo is a robust four-cylinder with a long service life expectancy. Misfires from defective ignition coils and injectors are the most common complaints. The engine requires the correct spark plug type PZFR5D-11. Check thermostat and cooling system at higher mileage.
City Sprinter in Mini Format
60 hp in the light Lupo — adequate for city use and short country runs. No fire, but no torment either.
Engine Weaknesses 5
The ignition transformer of the AUD fails and causes misfires on two cylinders simultaneously (1+4 or 2+3), since each internal transformer serves two cylinders. High-voltage flashovers are a common cause.
Symptoms: Engine warning light flashing, misfires on cylinders 1 and 4 or 2 and 3, hesitation, power loss
Injectors on the AUD can fail and cause misfires on individual cylinders that cannot be resolved by compression testing or ignition coil replacement. Leak-down testing is required for diagnosis.
Symptoms: Misfires on one cylinder, rough idle, engine warning light, high fuel consumption
The AUD engine specifically requires spark plug type PZFR5D-11. Other plug types may work briefly but cause misfires and increased wear in the medium term.
Symptoms: Misfires shortly after spark plug replacement, rough running, engine warning light
The thermostat of the Lupo 1.4 fails prematurely and sticks open or closed. With the thermostat permanently open, operating temperature cannot be reached.
Symptoms: Engine warms up very slowly, temperature gauge stays permanently low, heater delivers little warmth
The ignition coil of the AUD 1.4 16V shows hairline cracks at the connector and flashovers at higher mileages. Cracked coils cause misfires.
Symptoms: Misfires, shaking on acceleration, visible sparks at ignition lead, engine warning light