2012 128i Running Rough and Dealer Repair Question

I got a call last night from my wife. She was a couple miles from home and the car (2012 BMW 128i w/ 38k miles) was running rough and the service engine light came on. CPO car so I had it towed to dealer. Diagnosis: all 6 coil packs failed. New packs and plugs installed. This seems fishy. What would cause all six to fail? What could the real root cause be?

Thanks!

First guess is only one coil pack was bad, and the "standard" procedure is to replace them all.

If there's a common ground I'd be looking at that.

It likely needed only one coil, but lots of places really prefer to do all at once. Thinking is this- one failed, the others are the same age.

Or, If they are hard to get at, the labor might piss you off to do it twice.

Or, they are known trouble AND hard to get at, like the early COP Nissans.

Or, its a BMW, you must have lots of cash to throw away.

In reply to Streetwiseguy:

CPO, so only $50. But my time is valuable.

Standard operating procedure. One coil fails, can only assume the other 5 are close behind.

This plays right in to "my time is valuable". Do you want to take the car in 5 more times?

I've had customers do the one coil at a time scenario. Great money for me. I get to charge them $120 diagnostic each time and $120 to replace each coil vs one time diagnostic fee and one charge for replacing all coils.

Oh, the root cause? BMW/MINI and AUDI/VW can't source a quality coil to save their lives. The latest batch is from Delphi. Time will tell if they are any better than the Bosch and Behru they have been using.

If it's on their dime, I'd have them replace them all. Although the good news is that it shouldn't be awful on a straight 6.

Like you guys said, SOP. TSB for updated parts. Since it is a CPO, all were replaced with updated parts under warranty. Thanks for all the replies!

NEALSMO wrote: AUDI/VW can't source a quality coil to save their lives.

The Eldor ones from the Audi R8 seem to work pretty well.

/threadjack

Depending on the shop, they're also doing things by the book and if the book says replace all six then all six get replaced. Modern cars diagnose themselves pretty well and the solution is generally just parts swapping.