[Seanjohnson21]

I would like to start this off by thanking anyone who is reading this and willing to help. Also my apologies if these issues have been solved elsewhere in this forum. I searched both issues seperately and was unable to find a similar issue so I am creating this post to see if anyone may have a better idea of what is going on.


My car is a 2011 535i. It is completely stock and has about 90k miles on it. I purchase the car in December of 2022. Over the past 3 months ive ran in to this issue 4 or 5 times where my iDrive system display a message stating “drivetrain malfunction”. Using BimmerLink, I found these codes:

120408
Boost pressure control: shutdown as a follow-up reaction


11A210
Low fuel pressure system, plausibility: Electric fuel pump › output too high for actual pressure


The issue has only occurred at highway speeds and under acceleration. The car still drives semi normal, still able to reach high rpm range but feels as if the waste gate is stuck open so there doesn’t feel like there is any boost. After parking the car, turning off the ignition and waiting a few minutes the error is gone and the car feels completely normal again.

As far as I know, the low pressure fuel pump has never been replaced and based off of the codes it seems like that could be the culprit. Just want to research the issue thoroughly before spending 200$-400$ usd to purchase a new one. Thank you for your time

[SWFLf10]

I don’t know much about the fuel system, but that code leads me to belive the LPFP is at fault. I have 171,000 miles on my original one from 2015, but I don’t know what the general mileage is when they fail.

I would check around the air intake system for cracks or signs of leaks before purchasing anything though. Also look around by the boost pipe coming off the turbo and the upper and lower charge pipes. Could be something as simple as an old cracked part leaking air.

I’ve personally had issues where my charge pipe and boost pipe have come loose during high boost scenarios.