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Michaeluk, Technician
Category: Car
Satisfied Customers: 124
Experience:  Technician
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Sebastian I've replaced the high pressure fuel pump and have

Customer Question

Hi SebastianI've replaced the high pressure fuel pump and have had a little success but not enough to get the car back on the road.I can start the car by using brake cleaner in the air intake - the car can crank over and run idle for over an hour, however once I take it on the road it goes for about 500 metres and then cuts out. I then have to use brake cleaner to restart it - I now have an error code of P0088 - high pressure on the fuel rail - any ideas what I can do to get the car running normally again, please. Many thanks Ian
Submitted: 13 days ago.
Category: Car
Expert:  Michaeluk replied 13 days ago.

Dear customer, thank you for choosing Justanswer. My name is***** would like to help you I am a master mechanic with over 10 years experience with various car brands.

Unfortunately, my colleague does not seem to be able to answer your renewed request. However, I would like to try to help you.

The fault code says that the pressure in the distribution pipe is too high. There are various reasons for this.

A defective flow regulator on the pump is option number one. But I reject this possibility again, because you have replaced the pump and I do not expect that there is something defective in the new pump.

Possibility number 2 is a defective rail pressure sensor. This does not always have to be completely defective, but can also simply give an inaccurate value. If you have the possibility to read out the rail pressure with a diagnostic device when the engine is off but the ignition is on. This must be 0 bar. If the pressure deviates, either the sensor or the cable between sensor and control unit (internal resistance, corrosion) is the cause.

If the pressure is 0 bar, an injector return flow measurement should be made. If the rail pressure is too high, it can be expected that one injector will return significantly more or less fuel than the other injectors. The corresponding injector should then be replaced.