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Rough idle after intake install - N55

DDriftKing_M3

@driftking_m3

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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?

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  1. #1
    TTrackDayTom

    @track_day_tom

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    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

  2. #2
    DDetailingKing

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    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.

  3. #3
    NN54 Boost

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    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.

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