Fuel Control Mixture Rich Bank 1
1997-2000 BMW 528i E39 2.8L I6 🇬🇧
Description
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.
Related Codes
Other Powertrain Codes
- P0001Fuel Volume Regulator Control Circuit/Open
- P0002Fuel Volume Regulator Control Circuit Range/Performance
- P0003Fuel Volume Regulator Control Circuit Low
- P0004Fuel Volume Regulator Control Circuit High
- P0010Intake Camshaft Position Actuator Circuit/Open Bank 1
- P0011Intake Camshaft Position Timing Over-Advanced Bank 1
- P0012Intake Camshaft Position Timing Over-Retarded Bank 1
- P0013Exhaust Camshaft Position Actuator Circuit/Open Bank 1
- P0014Exhaust Camshaft Position Timing Over-Advanced Bank 1
- P0015Exhaust Camshaft Position Timing Over-Retarded Bank 1
P1084 on Other Vehicles
Common Questions
What does code P1084 mean on a 1997-2000 BMW 528i E39?
P1084 stands for "Fuel Control Mixture Rich Bank 1". 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.
What are the symptoms of P1084 on a BMW 528i E39?
Common symptoms of P1084 include: Check Engine Light, Black exhaust smoke, Fuel smell from exhaust, Rough idle, Poor fuel economy.
What causes P1084 on a 1997-2000 BMW 528i E39?
Common causes of P1084 include: 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.