BEWARE of Bosch Ignition coils made in Slovenia

[Sophisticated Redneck]

If you search the forums (here and Xbimmers) you will find several posts of problems with these coils. I too replaced all of mine last year with a set of Bosch coils made in Slovenia purchased from RockAuto and the thing could barely run, multiple misfire codes on 4 cylinders (N63 engine). I had to put the old ones back in (Original Bosch coils made in Germany) and then replaced with Eldors and have never had a problem.

The Bosch coils made in Slovenia ARE NOT THE SAME as the units made in Germany. At least not the batch that RockAuto has.

Also beware of fake Delphi coils, real Delphis are ok

Eldor Coils are EXCELLENT

Bremi Coils (just came out) seem to be good so far, they used to be BMW OEM before Bosch

How can you tell if they are real or fake? If you are only paying 20 dollars a coil, then they are shit. Real coils cost around 35-40 each, no way of escaping that. Non BMW branded Eldors can be picked up for 35-40 each, the ones with BMW stamped on it will cost you double. I believe ECS Tuning or FCP EURO has them. OEMBimmerparts has Eldors and Bremis. DONT BE CHEAP when it comes to coils.

As for plugs, generic Bosch platinum plugs are fine (about 7 dollars each), NGK Laser Iridium are the best (about 12 dollars each).