[roni21]

Hello please i need help with my bmw x6 n55 engine. I have got a check engine light with low boost and i have been chasing this for 4months now. I changes 3 turbos + charge pipe but still have same problem with code 2c57(Charge-air pressure control, lower value: Boost pressure too low). check the notepad file to get the link to my log

[Beard]

Hello.
Is the vacuum system OK?
Is the vacuum in the system holding?, or does the gauge needle drop immediately? If immediately after stopping the engine there is no vacuum in the system, then the vacuum pump should be replaced, having previously checked all vacuum hoses for leaks. There is a vacuum reservoir in the valve cover, if there is engine oil in it?, then this indicates wear on the vacuum pump. So it needs to be replaced. And first of all, you need to replace
Boost pressure converter - 11 74 7 649 407, it regulates the boost pressure. Turbine has nothing to do with it. It is also necessary to check the vacuum cylinder of the turbine for tightness.
The membrane should hold a vacuum, if the vacuum does not hold, then it is torn, which means that the vacuum cylinder must be replaced.

If my post helped you hit the thanks and reputation button. Thank you.

[bmchicago]

if your N55 is PWG, check the vacuum lines to see if they are swapped.

[roni21]

Hello.
Is the vacuum system OK?
Is the vacuum in the system holding?, or does the gauge needle drop immediately? If immediately after stopping the engine there is no vacuum in the system, then the vacuum pump should be replaced, having previously checked all vacuum hoses for leaks. There is a vacuum reservoir in the valve cover, if there is engine oil in it?, then this indicates wear on the vacuum pump. So it needs to be replaced. And first of all, you need to replace
Boost pressure converter - 11 74 7 649 407, it regulates the boost pressure. Turbine has nothing to do with it. It is also necessary to check the vacuum cylinder of the turbine for tightness.
The membrane should hold a vacuum, if the vacuum does not hold, then it is torn, which means that the vacuum cylinder must be replaced.

If my post helped you hit the thanks and reputation button. Thank you.

thanks for very much. Once the engine is offed, the vacuum gauge start dropping and before 10 seconds, it is all down to zero. There's no oil in the vacuum reservoir and i still can figure out if there's any leakage. My gears also take longer time to change

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if your N55 is PWG, check the vacuum lines to see if they are swapped.

Yes it is PWG and i recheck the vacuum lines and all good

[bmchicago]

how much vacuum you have at wastegate solenoid? and can u install a T fitting to the turbocharger so u can monitor vacuum inside vehicle when you are driving?

[Beard]

thanks for very much. Once the engine is offed, the vacuum gauge start dropping and before 10 seconds, it is all down to zero. There's no oil in the vacuum reservoir and i still can figure out if there's any leakage. My gears also take longer time to change
++++++++++++++++++++++++++++++++++++++++++++++++++++
Hello.
10 Seconds???
This indicates that you have a vacuum leak.
Most likely the vacuum pump is worn out. And how did you know that there was no engine oil in the receiver? To see this, you need to remove the valve cover and try to drain the oil from the receiver by placing the valve cover vertically so that the receiver fittings look down. Replace the pressure converter, it is responsible for the boost pressure!!!
When the engine is idling, the boost pressure should be approximately equal to atmospheric pressure.
approx. 10xx m.bar

If my post helped you hit the thanks and reputation button. Thank you.

[roni21]

thanks for very much. Once the engine is offed, the vacuum gauge start dropping and before 10 seconds, it is all down to zero. There's no oil in the vacuum reservoir and i still can figure out if there's any leakage. My gears also take longer time to change
++++++++++++++++++++++++++++++++++++++++++++++++++++
Hello.
10 Seconds???
This indicates that you have a vacuum leak.
Most likely the vacuum pump is worn out. And how did you know that there was no engine oil in the receiver? To see this, you need to remove the valve cover and try to drain the oil from the receiver by placing the valve cover vertically so that the receiver fittings look down. Replace the pressure converter, it is responsible for the boost pressure!!!
When the engine is idling, the boost pressure should be approximately equal to atmospheric pressure.
approx. 10xx m.bar

If my post helped you hit the thanks and reputation button. Thank you.

Oh i measured the vacuum pressure from the pipe that connect to the vacuum pump - the valve cover. What you are saying is that i will have to take off the valve cover to verify if there's any leakage. I have changed the boost pressure but still same problem. On a level land the car runs fine until when i push the pedal hard before getting limp mode

[roni21]

how much vacuum you have at wastegate solenoid? and can u install a T fitting to the turbocharger so u can monitor vacuum inside vehicle when you are driving?

Here is what i get after 20 seconds of car been on
The vacuum dropped immediately after the car is switch off
No there's no way to take the T fitting vacuum pipe inside the car

[bmchicago]

how much vacuum you have at wastegate solenoid? and can u install a T fitting to the turbocharger so u can monitor vacuum inside vehicle when you are driving?

Here is what i get after 20 seconds of car been on
The vacuum dropped immediately after the car is switch off
No there's no way to take the T fitting vacuum pipe inside the car

NO WAY? do you have no vacuum lines, masking tape, t-fittings? Cant roll down your windows, the doors dont open, they are welded shut?

just drive the car to the wrecker then.

[Beard]

Hello please i need help with my bmw x6 n55 engine. I have got a check engine light with low boost and i have been chasing this for 4months now. I changes 3 turbos + charge pipe but still have same problem with code 2c57(Charge-air pressure control, lower value: Boost pressure too low). check the notepad file to get the link to my log

Hello.
You don't want to listen to what they tell you.
Then learn the materiel yourself.
******************************************************* **********
You have already changed three turbines. This is from your words!!!
I think it's cheaper for you than to learn materiel. If you don't want to listen, then don't ask... Wasting time on you is pointless!!! Go to the supermarket and buy 10 turbines and change them every day.
It just won't change anything. If you don't want to listen to what they are talking about, no one will help you!!!
don't ask anything!
On your part, you didn’t even say thank you, for the fact that people are wasting their personal time trying to explain to you how it all works.
YOU do not hear it, do not see it, and are trying to explain to us that everything works for you. I don't understand! Why make a theme?

As my grandmother used to say -
Granddaughter! - what you want to eat, - I have already pissed!!!
_______________________________________________________________
Sorry, But maybe now you will read all the posts again and learn to Read and listen.!!!
Learn the materiel yourself!!!
A little advice for you. Open ISTA+ and read about D.V.S. and how it works! Then you don't have to ask!

If my post helped you hit the thanks and reputation button. Thank you