BMW E46 camshaft position sensor fault
E46 what do fault codes P0340-P0344 mean?
Codes P0340-P0343 concern the camshaft sensor circuit, and P0344 means an intermittent fault in it. P0344 points to the intake-side sensor. In BMW's own diagnostic software (INPA), code 65 is the intake-side sensor and code 18 the exhaust-side sensor.
What symptoms does a camshaft sensor fault cause in the E46?
A typical symptom is long cranking, uneven idle and weak torque. The intake-side sensor is a known weak point and often fails before 100,000 km, the exhaust-side one usually before 150,000 km. The fault does not always set a code.
How do you replace the E46 intake camshaft sensor?
The sensor is behind the VANOS solenoid (the valve that adjusts cam timing). Replacement is a DIY job of about 20 minutes: you need a 32 mm wrench, a 5 mm hex key and a 10 mm socket for the air filter housing. Make sure the wiring harness is firmly seated in the connector.
E46 code persists even though the camshaft sensor has been replaced?
The cause may lie elsewhere: the crankshaft sensor, the exhaust-side sensor, a broken timing chain or its parts, the VANOS solenoid or the wiring harness connection. Read the codes as a whole, not just a single code.