2011 128i, rough idle/shaking cold start, just had plugs changed! help

[Vancity128guy]

Originally Posted by NorthernDancer

Before you go buy Bosch coils, join BMW Club of BC. That "someone" should be a club member who will help you with everything on your car.

ok will do thank you

[E91WAG3N]

This is a known issue and BMW has a service bulletin for it. Their recommended fix is to replace all 6 coils and plugs. I had similar issues with my car and replacing all 6 plugs and coils resolved the rough idle and occasional check engine light. My car was at around 60-65k miles when it happened.

Edit: The coil is what causes the misfire. Replacing the plugs is more of a hey while you already have all the plastics off and coils out, may as well replace them while you're in there.

[Vancity128guy]

Originally Posted by ubersteuer

This is a known issue and BMW has a service bulletin for it. Their recommended fix is to replace all 6 coils and plugs. I had similar issues with my car and replacing all 6 plugs and coils resolved the rough idle and occasional check engine light. My car was at around 60-65k miles when it happened.

Edit: The coil is what causes the misfire. Replacing the plugs is more of a hey while you already have all the plastics off and coils out, may as well replace them while you're in there.

well they told me at the dealership just to replace them as they die.. im not under warranty either.. i had one replaced a year ago actually and im only having issues with them again now..

[E91WAG3N]

Originally Posted by Vancity128guy

well they told me at the dealership just to replace them as they die.. im not under warranty either.. i had one replaced a year ago actually and im only having issues with them again now..

Easy money maker for them. They prob charge an hour to remove and replace the valve cover plastics and cowl each time they do it.

Keeping the car long term, I'd rather knock the coils out every 60k as a maintenance item along with the plugs rather than having to deal with a individual failures every 6 months or year.

.....up to you.

[Havocsteve]

So far for myself, getting to 90k kms, only done spark plugs. Even then when I did them at 70k, they were still in great condition.

[nato-main-man-5am]

So is the consensus that if one coil is bad, might as well replace them all while you are in there? And if you are in there already, might as well do the plugs as well?

38k miles on my 2012 128i.

[nato-main-man-5am]

And someone mentioned coding the coils. I have Carly (with the upgrade to code for battery replacement). Can I do it with that?

[olds350]

Originally Posted by nato-main-man-5am

And someone mentioned coding the coils. I have Carly (with the upgrade to code for battery replacement). Can I do it with that?

On a 128 or 328 for that matter, there is no coding that needs to be done via Carly for coil replacements. Just swap out the coils and plugs and be done with it. To everyone else's point of trying to the do the work yourself, I highly recommend doing it yourself or finding a friend that is mechanically savvy to show you the way.

This really isn't a hard job. I just had to do all of this to my 128 because of an intermittent stutter and there were no codes. The bosch coils on these cars start to fail around 60-70k miles.

You'll need to remove the upper air filter housing so you can remove the plastic head cover. There's a ton of youtube vids on it. Once you have access to the coils, there's a simple flip lever that disconnects the wiring. The coil pack itself simply presses on top of the plug, there's no fastener holding it in. Just pull it up and out. Get a long extension and a spark plug socket and R & R the plugs. Make sure you put a small dab of plug rated anti seize on the threads. Torque to spec and reassemble.

What I write may seem simplistic, but really, that's it. I did all of mine coils and plugs for a about $250 plus a few hours of time. Add to the fact you have the satisfaction of doing it yourself. If I had to go to the dealer for every issue, I couldn't afford this nice car.

You never know if you can unless you try....

[nato-main-man-5am]

Very true. It took a few minutes to get to them, but once there, it's straightforward. I would say, set aside an afternoon if you haven't done it before, but it's more to allow time to review videos about each step, rather than because it is particularly complicated.

(The hardest part for me was fitting the cabin filter tray back in. A very simple low tech item, but it took me a few tries to get the angle right and if you haven't messed with a particular piece before, it's not clear what's fragile and what's strong and what can be pushed and what shouldn't, initially, so going slow can have advantages.)