Fuel Rail Pressure Deviation
1999-2000 BMW 323i E46 2.5L I6 🇬🇧
Description
The DME detected that the actual fuel rail pressure deviates significantly from the commanded fuel rail pressure. The high-pressure fuel system is not maintaining the target pressure requested by the DME.
Symptoms
- Check Engine Light
- Loss of power
- Engine hesitation
- Hard starting
- Rough running at various RPMs
Common Causes
- Failing high-pressure fuel pump
- Clogged fuel filter
- Leaking fuel injectors
- Fuel pressure regulator failure
- Low-pressure fuel pump weak
Diagnostic Steps
- Monitor commanded vs actual fuel rail pressure with scan tool
- Test low-pressure fuel pump output
- Inspect fuel filter condition
- Check for fuel injector leaks
- Test high-pressure pump output
Repair Notes
Replace the failing fuel system component causing the pressure deviation.
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
P1189 on Other Vehicles
Common Questions
What does code P1189 mean on a 1999-2000 BMW 323i E46?
P1189 stands for "Fuel Rail Pressure Deviation". The DME detected that the actual fuel rail pressure deviates significantly from the commanded fuel rail pressure. The high-pressure fuel system is not maintaining the target pressure requested by the DME.
What are the symptoms of P1189 on a BMW 323i E46?
Common symptoms of P1189 include: Check Engine Light, Loss of power, Engine hesitation, Hard starting, Rough running at various RPMs.
What causes P1189 on a 1999-2000 BMW 323i E46?
Common causes of P1189 include: Failing high-pressure fuel pump, Clogged fuel filter, Leaking fuel injectors, Fuel pressure regulator failure, Low-pressure fuel pump weak.