We just added nineteen new control units Pierburg to our stock. These units are in OE quality for almost all fuel pumps in modern cars with FSI / TSI / TFSI / TDI engines. All nineteen units cover the need of more than 10 million cars, whereas we will be extending the range of our supply…
How does control unit of the fuel pump works
Control unit is dealing with the effective fuel distribution. Thanks to the signal CAN-Bus with wide pulsing modulation it controls fuel pump in fuel distributing module. Main asset of this control unit is the optimal distribution of the fuel, which then is used in the amount needed for smooth engine operation. The effect of the control unit is the lowering of the needed power, saved fuel and last but not least better environment affect.
Engine without regulated fuel distribution (control unit) fuel pump is always working in full power. Unused fuel is going back to the tank. It makes the fuel temperature rise up and it causes vapour locks.
Regulated distribution fuel principle:
Fuel goes thanks to the fuel module from the tank through the low pressure tubes to the high pressure pump. During normal operation the pressure of the fuel is somewhere in between 0,5 up to 5 bars. With cold start it makes the pressure rise up to the 6,5 bars which leads to the higher starting pressure of the high pressure system and faster engine start. On the other hand start of the heated vehicle higher pressure stops the process of vapour locks.
- Pressure sensor (high pressure)
- Injection nozzles
- High-pressure pump
- Pressure sensor (low pressure)
- Fuel filter with pressure regulator
- Bus signal
- Pulse width modulation signal
- Engine control unit
- Fuel pump control unit
- Fuel delivery module
Advantages of the regulated system of fuel distribution:
- Only the required amount of fuel is supplied
- The fuel is heated less, reducing the risk of vapour locks
- Noise reduction
- More green – environmentally economical
- Reduced power consumption, resulting in fuel savings
When and how to change the control unit of the fuel pump, possible damages
If you see the downfall of the car power, loss of the pressure, car is switching into the emergency mode, couldn’t start the engine or the start light is on, it could signalize that control unit is damaged. Some of these states can indicate e.g. defect on the fuel pressure control, damaged cables, clogged fuel filter, fuel pump and empty tank. If the damaged control unit will be the case you need to think about replacement.
Every unit is specific for the exact car and engine. While ordering a new control unit see also the state of the software – picture above. It always has to be the same or higher than the original unit.
More details can be found in this PDF document Control units for fuel pumps - advices for replacement (link will open in new tab; doc size 472kb)