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L3g10n4rU
21-07-2017, 12:31 AM
Hello what could cause too high pressure on the fuel rail?
I have 482 bar (should be 210-290 bar) at idle and can't find the fix. Violent shaking at idle with warm engine. No errors.
Injectors are good on 13-14 and 72-77 channels.
mvb 022: 756rpm; 482 bar spec; 482 bar meas; 26-28% valve
mvb 023: 756rpm; 482 bar spec; 482 bar meas; 40-42% valve
After I run the car for a while, at idle I have the normal pressure of 230 bar with valve 20% on mvb 022 for max 4 minutes and than suddenly raises to 482 bar with no error!
I have changed the rail fuel pressure regulator and no changes.
Could a bad egr valve cause too high rail pressure? I have it at 80-95% all the time. Some ideas? Thanks!
This is how my car is acting at idle with 482 bar fuel rail pressure:
Audi a6 2.7tdi shaking engine problem 2 - YouTube (https://m.youtube.com/watch?v=lyA7HHjT5gU)

Audi a6 2.7tdi shaking engine problem - YouTube (https://m.youtube.com/watch?v=GNGYL0sSXaI)

I also have theese readings at idle:
33665
33666


33668

Alan02
21-07-2017, 10:57 AM
The fuel rail sensor could be giving incorrect info hence why new regulator hasn't rectified problem.

L3g10n4rU
21-07-2017, 11:13 AM
So what you are saying is that the sensor could transmit less voltage at idle to the ecu and ecu puts engine in controle mode? I don't know how to measure voltage to it but shouldn't it pop up an error saying low voltage coming from sensor? As far as I know from SSPes the reading should be between 0,30-4,5 volt for the sensor. Could n290 create this high pressure problem? When doing output testing, the n290 moves smooth from min to max. Just tring to find the solution without spending money fir pieces not needed to be changed like he pressure regulator.

Alan02
21-07-2017, 08:23 PM
I couldn't give you readings from a sensor. My point was, if it's faulty in any way, your regulator will only operate with what info it's given by ecu. Wrong info in = wrong info out. There will be a series of tests for it but unless you know them... good luck.

L3g10n4rU
26-07-2017, 02:17 PM
Well it wasn't the sensor since I changed it and I still have the same pressure 482 bar. Someone with another ideea please? Who builds such a big pressure on the rail? Could the high pressure pump be defective?