[BMW335XD]

Hello , I have a 2013 F30 335D with 70k km and I'm just after getting a downpipe and turbo back exhaust with dummy boxes to pass the MOT inspection. The car has 0 fault codes aside from this one. It is the first time I've ever seen it , started right after the new exhaust system. I was driving the car hard on the motorway over 200kmh pulling through the revs 4-5k rpm. I scanned the car with obd11 when I stopped for food and the code logged was:

"Boost pressure sensor signal too high
Manufacturer Specific fault code : 25CE00
Generic OBD2 code : PO238


Is it down to a lack of back pressure now maybe? I'm not sure where to begin but 0 issues before this. The car is remapped and I had the map adjusted by my tuner to suit the new downpipe and exhaust so abit up on power too probably but the code logged prior to the retune too. It logged again today for the 2nd time when I drove it hard again.

[Watsey]

The downpipe and exhaust shouldn’t have any direct effect on boost pressure. There will now be less back-pressure, but that’s normally a good thing.

I’d go back to your tuner that did the remap. Boost pressure sensors will be monitoring pressure in several places, including before and after the leak intercooler, and it sounds like the pressures are exceeding the programmed range.

Have you logged the boost readings and rpm ?

[BMW335XD]

The car is going back to the tuner now on Tuesday to see what he can do about it, hopefully it is just a map issue like you said and can be easily fixed. The error code states "4000 mbar limit reached" but I haven't got the proper software to log stuff myself. I will update after to see if he fixes it. thanks

[barf]

Remap problems or you messed up the vacuum lines running to turbos when you removed the DPF but then it shouldn't overboost that high anyway.
I know how painful removing that DPF is on the 335xd...

[cezar22]

Originally Posted by barf

I know how painful removing that DPF is on the 335xd...

Honestly really not that bad at all. And my god the engine bay is roomy with it gone.

EDIT: Oops sorry I didn't realize the OP car IS the 335.