P1083moderate severityPowertrain
Fuel Control Mixture Lean Bank 1
on 1996 BMW M3 3.2L I6 S52 · RWD
What this code means
The DME detected a lean fuel mixture condition on Bank 1 that exceeds the long-term fuel trim correction range. This indicates the engine is receiving too little fuel or too much air on Bank 1, and the adaptive fuel trim has reached its compensation limit.
Symptoms
- Check Engine Light
- Rough idle
- Hesitation on acceleration
- Poor fuel economy
- Possible misfire at idle
Common causes
- Vacuum leak on Bank 1 intake side
- Weak fuel injectors Bank 1
- Low fuel pressure from fuel pump
- Faulty MAF sensor under-reading airflow
- Cracked intake boot or DISA valve failure
Diagnostic steps
- Check for vacuum leaks using smoke test
- Monitor short-term and long-term fuel trims on Bank 1
- Test fuel pressure at rail
- Inspect intake boot and DISA valve
- Test fuel injector flow rates
Repair notes
Repair vacuum leaks first, then check fuel delivery components if trims remain lean.
Other Powertrain codes on this vehicle
P0001
Fuel Volume Regulator Control Circuit/Open
P0002
Fuel Volume Regulator Control Circuit Range/Performance
P0003
Fuel Volume Regulator Control Circuit Low
P0004
Fuel Volume Regulator Control Circuit High
P0010
Intake Camshaft Position Actuator Circuit/Open Bank 1
P0011
Intake Camshaft Position Timing Over-Advanced Bank 1
P0012
Intake Camshaft Position Timing Over-Retarded Bank 1
P0013
Exhaust Camshaft Position Actuator Circuit/Open Bank 1
P0014
Exhaust Camshaft Position Timing Over-Advanced Bank 1
P0015
Exhaust Camshaft Position Timing Over-Retarded Bank 1