P3657high severityPowertrain
GDI Fuel System Priming Pump Performance
on 2013 Audi A6 3.0L Supercharged V6 · AWD
What this code means
The low-pressure electric fuel pump that primes the GDI high-pressure fuel system is not delivering adequate fuel volume or pressure to the HP pump inlet.
Symptoms
- Extended cranking time
- Hard start after sitting
- Fuel rail slow to build pressure
- Engine stalling after start
- HP pump cavitation noise
Common causes
- Weak fuel pump motor
- Clogged fuel filter
- Fuel pump check valve leak
- Fuel tank pickup sock restricted
- Fuel pump relay intermittent
Diagnostic steps
- Measure fuel pressure at HP pump inlet
- Test electric fuel pump current draw
- Check fuel filter restriction
- Test fuel pump check valve hold pressure
- Inspect fuel pump relay and wiring
Repair notes
Replace low-pressure fuel pump or fuel filter. GDI systems are sensitive to feed pressure - even slight deficiency causes HP pump issues.
Other Powertrain codes on this vehicle
P0001
Fuel Volume Regulator Control Circuit/Open
P0001
Fuel Volume Regulator Control Circuit/Open
P0002
Fuel Volume Regulator Control Circuit Range/Performance
P0002
Fuel Volume Regulator Control Circuit Range/Performance
P0003
Fuel Volume Regulator Control Circuit Low
P0003
Fuel Volume Regulator Control Circuit Low
P0004
Fuel Volume Regulator Control Circuit High
P0004
Fuel Volume Regulator Control Circuit High
P0010
Intake Camshaft Position Actuator Circuit/Open Bank 1
P0010
Intake Camshaft Position Actuator Circuit/Open Bank 1