Fuel System: Common Problems

Common Fuel System Problems. Here are problems and solutions. Read this and avoid the problems. In addition, you become an expert in troubleshooting fuel systems.

With over 10 years of professional experience with fuel systems in particular, most problems have passed through customer service and the workshop. Here we list some common problems and tips on possible solutions:

1. Fuel pressure dip at throttle
2. Fuel pressure do not reach over "x" bar
3. External fuel pump sound wierd
4. Fuel leakage during sharp turns
5. Injectors have 100% duty but they should flow enough
   

Fuel pressure dip at throttle

• Leakage between in-tank fuel pump and fuel pump holder.
• Clogged fuel filter
• Low voltage to fuel pump
• Diaphragm in fuel pressure regulator
• Gauge show the wrong values

Fuel pressure do not reach over "x" bar

• Clogged fuel filter
• Clogged tank ventilation / breather
• Gauge show the wrong values

External fuel pump sound wierd

It is a common scenario that the fuel pump sounds a bit noisy / "uneven". Then there is often air in the system.

• The fuel pump sits too high in relation to the fuel tank
• The fuel pump sucks air
• The fuel pump is bad
• Pre-filter/internal filter clogged (try running the pump in reverse for a while and see if it helps.)

Fuel leakage during sharp turns

• One or two spirals can be made on the ventilation tubing to counteract this.
• The tank ventilation must be moved towards the center of the tank.

Injectors have 100% duty but they should flow enough

• Clogged injector filter
• Clogged fuel filter
• Fuel pressure too low
• Low voltage to fuel pump
• Diaphragm in fuel pressure regulator
• Leakage between in-tank fuel pump and fuel pump holder.
• Clogged tank ventilation / breather
• The fuel pump is bad