is this an n54 or n55?

Just curious from a rough idle diagnosis. N54s have leaky injectors, fuel pumps, carbon build up and plugs / coils as possible culprits. N55s less of those issues.

When I did coils, I did all 6 along with plugs. It is an easy, DIY, but it also seems like your indy is charging fairly, so it might just be worth it... especially if you're planning on holding on to it for a while.

2011 N55.

It could be plugs/adaptation, it could be injectors, it could indeed be the coils...

His labor at $100 is not bad. But his coil prices are high, so I think I'm going to DIY. They just pop in, it seems.

Do you guys use dielectric grease when you put in coils? Rubber on rubber?

I have never used dielectric grease on coils. then again I never used it on cars that had plug wires either.

I just had one fail... (well, John did) and I'm going to go all 6. Peace of mind.

Diagnostic fee is probably in the $120-150 range.

I wouldn't feel unethical at all. If anything, dealers should feel unethical for raping the many customers for charging exorbitant fees for work that a monkey can do.

My opinion, of course.

Yes, I have always used it - both when I had standard coil/distributor/leads as well as 'coil on plug'. Just a little bit keeps things going in easy and (I think) when it comes time to do it again in the future - easy off too.

And yes, I'd do all 6. I would be sure to use all the same brand/PN of coil - if you break up who is doing what. And - I would also do the same with the plugs and connectors as well.

I use dielectric grease when I push the rubber part into the spark plug itself. It makes it easier and provides good contact.

If using BMW replacement parts, make sure it is the "coil of the month" - BMW can't make up their mind which manufacturer they dislike least. Currently they are using Delphi coils. Here's the complete supersession history:


https://www.glaver.org/transient/8616153.png

Note: The part number carries a precaution that it contains hexahydro-4-methylphthalic anhydride which is apparently Not Good For You. This is a BMW AG warning, not a California Prop. 65 one, so possibly for real. Do not eat. :rolleyes:

Thanks, Terry. My research indicated that the coil du jour was Delphi as well. That was also what my mechanic was going to use.

Last night I ordered a six-pack of Delphi on FCP Euro. The site says it fits my car. They were so reasonable in price $155 for all six, I'm suspicious that there is 'delphi' and there is 'delphi'.

https://www.fcpeuro.com/products/bmw...12138616153kt1

At that price, it can't hurt (given that it's looking easy and I'm going to DIY).

Do you have a garage / workshop at your new(ish) place? If not, do you want to come over here to work on it? I'm pretty sure I have the right size spark plug wrench, as well as all of the usual tools. Just let me know - I'm working on the Sat/Sun overnight, so those days are out. And I need some warning to have my tenant move some of his cars (AKA "clown car" and "rustbucket") so you can get into the garage.