Drivetrain Malfunction - N63TU 50i 51k miles

[RotaryPowered]

Not looking for assistance, just adding to the knowledge and experience base.

This past weekend driving home on the freeway at a spirited pace (85mph+) I felt a slight loss in power, knew something was off immediately and probably a second later the drivetrain malfunction light came on. Had a horrible vibration and loss of power, but was only a couple miles from home at this point so I continued on home.

Ran the codes with OBDII and BMW phone app and got Cylinder 3, Cylinder 7 misfire. Took it to the dealer and was quoted for new plugs, coils, software update and air filters.

Couple of things, I'm a little confused why they didn't go ahead and change the plugs and coils at my last service as I thought this was part of the 50k service. When I asked the SA, he said that they don't do any work to these cars until they are needed other than oil changes. Essentially "the car tells us what it needs and that's when we do it"

Also, requested a transmission flush and the dealer flat refused with the normal lifetime fluid line.

Just sharing in case someone runs into a similar issue and needs a little reassurance that its not something major like I did!



Actually one question/comment. I've had the car in for service 3 times in the last couple weeks, first to fix a seat trim piece, then a nail in tire, then this issue. I've driven 3 different loaners, a 330i, X4 M40i and this time an X5 40i s drive. These all seem to shift much smoother and better than my X5 50i, is this software, newer transmission design, maybe related to the transmission flush?? Just curious if anyone knows.

[1norseman]

Last time in the shop for drivetrain malfunction, I had them replace all the coils. Only one was bad, but I figured might as well get them all done (hot vee design, and they all suffer from the same heat soak).
About 80k miles on mine at the time, and they gave me an X4 as a loaner. I noticed the same thing. Shifting felt different, smoother.
Once things go back to normal, I plan to get my transmission fluid changed, see if that changes anything.

[Sophisticated Redneck]

N63 & S63's and all TU variants will eat coils depending on how you drive. If yours is a daily driver, stuck in stop and go, short trips, idling for long periods of time, etc then they wear faster due to heat soak (as does everything else in the engine compartment).

As for the transmission, you can find a thread I started a month or so back (and there are many other similar threads), ZF clearly states to change it, BMW is full of crap. It's just a marketing gimmick from them. Take it to a good Indy shop, change the fluid & filter (or do it yourself, not a bad job to do), then have them reset the transmission adaptations. After a short learning procedure, it will shift much smoother

[BobBeau]

Originally Posted by Sophisticated Redneck

N63 & S63's and all TU variants will eat coils depending on how you drive. If yours is a daily driver, stuck in stop and go, short trips, idling for long periods of time, etc then they wear faster due to heat soak (as does everything else in the engine compartment).

As for the transmission, you can find a thread I started a month or so back (and there are many other similar threads), ZF clearly states to change it, BMW is full of crap. It's just a marketing gimmick from them. Take it to a good Indy shop, change the fluid & filter (or do it yourself, not a bad job to do), then have them reset the transmission adaptations. After a short learning procedure, it will shift much smoother

Are there different variants of coils? Anything better than the stock coils?

[turboawd]

It boggles my mind that bmw still has coil issues

[Sophisticated Redneck]

Originally Posted by BobBeau

Are there different variants of coils? Anything better than the stock coils?

I have tested: Bosch (Germany), Bosch (Slovenia), Eldor, Delphi, and Bremi.

Eldor are my favorite, running them now and I have the ESS tune on mine and no issues at the higher boost. They are heavier and have the best build quality then all the rest IMO and you can pick these up from FCPEuro. Bremi appear to be good too . Delphi is a mixed bag, alot of counterfeits. Bosch (Germany) are ok and OEM. BUT Bosch (Slovenia) ARE JUNK. Avoid at all cost.

Expect to pay around 30-40 dollars a coil. If you find coils for 20 dollars each or something, you can bet they are counterfeit junk.

[BobBeau]

Originally Posted by Sophisticated Redneck

I have tested: Bosch (Germany), Bosch (Slovenia), Eldor, Delphi, and Bremi.

Eldor are my favorite, running them now and I have the ESS tune on mine and no issues at the higher boost. They are heavier and have the best build quality then all the rest IMO and you can pick these up from FCPEuro. Bremi appear to be good too . Delphi is a mixed bag, alot of counterfeits. Bosch (Germany) are ok and OEM. BUT Bosch (Slovenia) ARE JUNK. Avoid at all cost.

Expect to pay around 30-40 dollars a coil. If you find coils for 20 dollars each or something, you can bet they are counterfeit junk.

You have a part # for those eldor's?

[Sophisticated Redneck]

Originally Posted by BobBeau

You have a part # for those eldor's?

Sure, here is a link: https://www.fcpeuro.com/products/bmw...or-12138657273. FCP lists this incorrectly as not working with the F15 but it works perfect with the F15 35i, 50i or M.

Protip when replacing your coils: Turn the coil side to side before releasing it and pulling it out. You can only rotate it a 1/8 of an inch or so back and forth as there are guides on the valve covers to ensure the coil is installed correctly but this small movement will help break the coil free from the spark plug and make it much easier to remove. Your fingers will thank you.

[Thecastle]

Originally Posted by turboawd

It boggles my mind that bmw still has coil issues

I'll say my 4 gasoline BMWs over the last 8 years I've only had 1 coil pack that went bad. 28 coil packs total.

Own - 2011 X5M 61K miles 20K miles towing, and on original coils (S63)
Own - 2016 550i 70K miles no coil pack failures (N63TU)
Own - 2013 Mini Cooper S 39K replaced 1x coils for rough idle (N18B16)
Owned - 2008 X5 4.8i 96K miles original coil packs, 10K miles of towing. (N62)

total owned 28 BMW coil packs 1 failure.

So other than the mini the BMW coil packs seem fine. I suspect there have been some bad ones in the past, a lot of companies had problems in the oughts. Those who tune their cars will see more failures. But for me at least the coil packs have been fine. Though I will mention they are very easy to mis-seat and can act like their bad, but re-seating fixes this. Experience from changing plugs. but not saying they don't fail.

[AZTWW]

Don't let them update the software on the X5 if you plan on a tune. The latest update blocks it.

[RotaryPowered]

Apparently they didnt put something back together correctly, was just driving down city street (maybe 45mph) and drivetrain malfunction back on, code read low boost pressure, so guessing pressure leak due to not putting shit back together correctly.......

Code 120708
Boost pressure control 2, plausibility: pressure too low

[RotaryPowered]

Its back at the dealer. They couldnt find anything obviously disconnected or leaking, so they are going to perform a smoke test.

[RotaryPowered]

Dealer found a split vacuum line that they would have to remove to do the plugs/coils, so they are covering the cost.

[CT335xi]

Originally Posted by RotaryPowered

Dealer found a split vacuum line that they would have to remove to do the plugs/coils, so they are covering the cost.

That’s the least they should be doing for your inconvenience, hopefully all will be well once you get it back!

[RotaryPowered]

Originally Posted by CT335xi

That’s the least they should be doing for your inconvenience, hopefully all will be well once you get it back!

Went to pick it up and check engine light was still on... they forgot to plug in the mass air flow sensor. But after fixing that last piece all is well and car runs great.

[Chicane_S54]

Originally Posted by BobBeau

Are there different variants of coils? Anything better than the stock coils?

Yes. The Delphi coils (Silver) which, I believe, are stock have that nice click when you install and the Bosch coils (black) which have no click but which actually have better connectivity. I preemptively replaced mine with the Bosch coils (42K)...just to be sure....