BEWARE of Bosch Ignition coils made in Slovenia
 

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).

I will caution people that 'upgrading' plugs to 'non OE designs' can cause issues. Especially with forced induction (aka turbo).



People have used the online 'recommended upgrade' that various vendors list for specific models, and have chased misfires due to this. Just FYI


:thumbup:

What I learned
 

I had a miss on cylinder 5 on my 2007 4.8l X5. I replaced the coil with Bosch made in solvenia, actually 3 different ones and they all missed just like the original bad coil. Then I put in an original part number one from a 2004 3 series I have and bingo all was good! Here is the wild thing I took one of the new solvenia coils which would miss in my X5 and put it in my 3 series and it works there! ........ conclusion the X5s are somehow picker about the coils or require old part numbered ones where E46 3 series works with either! See my thread about bad coils in the last week for more

What do people think about the BavAuto "High Performance" Ignition Coils?
For some reason it lists just about every N63 engine model as compatible, except for E70 X5 50i. Has anybody tried them? If yes, is it worth the money?

Better to spend the money on oxy.



Seriously, you are pissing money away.

That seems to be the consensus on other boards as well.

Just wish there were better after-market coil packs. The BMW ones seem to only last 30-50K miles for me.

its possible you just had a bad batch.. i used slovenia made coils in my 335 and now in my x5m and didnt have problems in either car. In general, on the these turbo cars coils seem to have a shelf life of 50-70k in my experience due to all the heat cycles. Dont know if Eldor coils last longer but i have heard good things

anyone figure out if it really is slovenia-made...or are their counterfeits in the market?

Yikes, definitely staying away from those.