Complaint: Drive Characteristic Faults, Lack Of Power
WARNING: This page does not describe the selected car, but rather 16 other vehicles, including the 2006 BMW 325Ci, 2005 BMW 325xi, 2005 BMW 325i, 2005 BMW 325Ci, and 2004 BMW 325xi. However, it is still accessible from the selected car via links, so may be relevant.
- Run engine at idle speed and measure fuel pressure.
If The Measured Value Is Less Than The Nominal Value - 0.2 Bar:
- Line cross-sections in fuel feed are constricted or fuel filter is clogged, or fuel pump voltage supply is not O.K.: e.g. as a result of high contact resistance (corrosion) in plug connection between wiring harness and fuel pump.
If The Measured Value Is Greater Than The Nominal Value + 0.2 Bar:
- Turn off engine stop and then observe measured value.
- If measured value drops to nominal value, then line cross-sections in fuel return are constricted or clogged.
- Check the fuel lines for kinks.
If no kinks are visible:
- Replace return lines
If measured value remains too high, then pressure regulator is in all probability faulty.
IMPORTANT:
With less likelihood, the return line may be completely blocked. When the pressure regulator is removed, fuel could escape under pressure!
- Have a cleaning cloth ready and catch and dispose of escaping fuel.
- Replace the return line but not the pressure regulator.