About an experience servicing my car

[pitosalas]

(I hope this is the right subforum but not really sure)

I took my 2011 BMW 335Xi in for mandatory recall repairs - "Short Harness Repair" and "Vanos Gear Bolts". When I picked it up, around 5 minutes after driving away, a big scary error icon lit up (looks like an engine that has a diagonal line through it) that said the car would be running with reduced performance and take it back. Which I did.

They said that they found "Misfires present for cyl 5-6. Removed coils to inspect. Found both to have aged rubber seals to be not seating correctly. Massaged rubber and moved coils to col 1-2. Using screw drive and pick moved ribber in place and seated coils. If the issue persists replacement of coils is necessary."

I don't know what all that means. Since the problem occurred right after the recall do you think that one could have triggered the other? And is needing replacement coils a logical conclusion and would it be expensive?

Anyone knowledgable about this stuff? It goes over my head!

[MauiM3Mania]

Moved from the General BMW Discussion sub-forum.

[Pilgrim]

I can tell the OP doesn't know much about cars, which is OK. But saying it's over your head is a cop-out. Do some reading in this forum to learn more about cars, and by becoming better informed you will be better able to make good decisions about your car's maintenance and repair.

No, the misfires have nothing to do with the other work. Coils and spark plugs provide ignition to burn gas. They moved the coils to a different set of spark plugs to see if the misfires move with the coils. If they do, it's bad coils. If not, it's the spark plugs. Standard maintenance maneuver, and a good idea to get information for you.

[jclausen]

You need to take it back to the dealer and have them check there work before starting any dx. If you are not comfortable or really don't want to or know how to work on you car then don't, take it to a good bmw independent shop.

[White94RX]

It sounds like he did take it back and they fixed it.

Probably what happened, was they pulled the coils out, and valve cover off to do the vanos gear bolt repair. Upon reinstallation, they probably weren't seated properly, or even the rubber at the top that goes over the edge of the metal of the head pushed up. Eventually the coils came unseated and misfired. They swapped the coils to other cylinders, seated them properly (hopefully) and all is well. If not, the coils would need to be replaced. If they're original Bosch coils, they're probably on their last leg anyway, and should probably all be replaced with the updated Delphi coils.