[bobbby]

2011 e90 N55

Anyone have experience with these codes? Tried clearing them out but they came right back. This happened shortly after I flashed from mhd stage 1+ back to map 0 so I could get smogged in CA.

[dpaul]

Two possible candidates are MAP sensor and pressure converter (boost solenoid). Because you get both high and low pressure issues, I'll bet on the solenoid.

Alternatively, flash back to stock, not just map 0

[bobbby]

Originally Posted by dpaul

Two possible candidates are MAP sensor and pressure converter (boost solenoid). Because you get both high and low pressure issues, I'll bet on the solenoid.

Alternatively, flash back to stock, not just map 0

Thanks man. Should I just replace these items or is there a way to pinpoint the exact failure point beforehand?

[bobbby]

Solved:

Took it into an indie and they were able to reset adaptations according to a bulletin to get rid of the 28A0 and 2820 codes.

The 2c57 would not go away despite trying a working boost solenoid, smoke test, and cleaning the map and maf sensors. They said it might be the stock tune building too low boost due to the larger aftermarket intercooler. So I went to pick up, reflashed to stage 1+ and the 2c57 has gone away.

Apparently you don't need to flash map 0 to pass smog if you have still have cats.

[dpaul]

Originally Posted by bobbby

Solved:

Took it into an indie and they were able to reset adaptations according to a bulletin to get rid of the 28A0 and 2820 codes.

The 2c57 would not go away despite trying a working boost solenoid, smoke test, and cleaning the map and maf sensors. They said it might be the stock tune building too low boost due to the larger aftermarket intercooler. So I went to pick up, reflashed to stage 1+ and the 2c57 has gone away.

Apparently you don't need to flash map 0 to pass smog if you have still have cats.

Nice!