Rough idle after intake install - N55

2 months ago· 17 posts

Installed a new cold air intake on my N55 335i and now the car has a rough idle. It hunts between 600-800 rpm and sometimes stalls. Drives fine once moving. I checked for vacuum leaks but cant find any. Could the MAF sensor be confused by the new intake? Should I do an adaptation reset?

3 791

Replies (3)

TrackDayTom

2 months ago#1

this happened to me too. the ECU went into a safe mode. i had to use ISTA to do a full flash recovery. took about 2 hours but the ECU was fine afterwards

11 posts · 0 rep

DetailingKing

2 months ago#2

ALWAYS plug in your laptop when flashing. This is rule #1. Hope you can recover it. Most ECUs can be recovered via bench even if OBD doesnt work.

11 posts · 0 rep

N54 Boost

2 months ago#3

Dont panic! The ECU is probably not bricked. You need to do a recovery flash via bench (not OBD). Find someone with a bench tool like KTag or CMD Flash who can recover it.

24 posts · 0 rep

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