Hi, I'm new tp the forum and new to a BMW, I've always wanted an E46 and a couple of days ago i brought one.
Before i bought it the dealer told me the MAF sensor had just been changed because it was faulty. When i test drove the car it was fine.
On the drive back (Where i bought it from was about 60 miles from where i live) it started to cough or seemed like a misfire while cruising at about 80mph.
Today i discovered its doing the same thing while I'm trying to accelerate (When i get past about 2000rpm, before 2000 it seems fine)
The idle is fine and never misfires when idling, but i can sit there and just rev it and again after 2000rpm it stutters and misfires.
But if you keep your foot down it gets past the misfire range and revs onto 3000rpm and upwards fine. Its only within that specific rev range it occurs.
As the dealer is quite a way from me i toke it to a local garage who did a diagnostic and found the MAF sensor readings are way off what they should be.
They said the new MAF thats been put on is a cheap jack aftermarket one, so it could either be that, or the wiring in-between the MAF and the ECU.
So the dealer is paying for me to get a proper bosch MAF sensor as a replacement, i can either fit it myself or drive the 60 miles back to him to have him do it.
I am capable of fitting it myself, however i would rather a proper mechanic so it and test it again and make sure all is well.
Is it possible that one of these cheap aftermarket MAF's could fail that quickly? I mean it can't have been on there for more than 50 miles. Or is it possible its something more serious?