P1084moderate severityPowertrain
Fuel Control Mixture Rich Bank 1
on 1996 BMW M3 3.2L I6 S52 · RWD
What this code means
The DME detected a rich fuel mixture condition on Bank 1 that exceeds the long-term fuel trim correction range. The engine is receiving too much fuel or insufficient air, and the adaptive system can no longer compensate.
Symptoms
- Check Engine Light
- Black exhaust smoke
- Fuel smell from exhaust
- Rough idle
- Poor fuel economy
Common causes
- Leaking fuel injectors Bank 1
- Faulty O2 sensor Bank 1 reporting false lean
- High fuel pressure
- EVAP purge valve stuck open
- Crankcase ventilation valve (CCV) failure
Diagnostic steps
- Monitor fuel trim values on Bank 1
- Test O2 sensor response Bank 1
- Check fuel pressure regulator
- Inspect EVAP purge valve operation
- Test CCV valve for proper sealing
Repair notes
Replace faulty O2 sensor or repair fuel delivery issue causing rich condition.
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