[TEST DRYVER]

So I was out of the country with my wife and daughter for 2 weeks. I recently acquired a 2015 335i M-sport with adaptive suspension for my wife (its our family car, but I still drive it about half the time). I've had the car for about 2 months, and started ordering parts from Mike at Extreme Power. I picked up an AR design catted downpipe, VRSF charge pipes, CSF fmic, BM3 stage 2 tune, BM3 OBD agent device, VMR wheels and Michellin PS4S tires. I had the parts installed at my local tuner shop while I was out of town. When I got back to town, I picked up my car, excited of course, drove it around, enjoying it.
One night I was messing with my tune parameters, I took my car out into the open desert to test it out (I live just outside of Phoenix, in AZ) on a windy road with long sweepers. I stopped in the middle of the road to perform a launch (it was 11pm in the open desert), I messed up the launch sequence, as I've done in the past (before the mods were applied), the rear tires tried to brake loose while the front brakes were on (like I said, it didn't go into launch control mode), and before I could let off the gas, I heard a loud thump! The sound came from the back of my car, I thought I blew my transmission or differential. The car was still spinning the axle in the rear, I couldn't get it to stop. The car wouldn't go in park, drive, reverse, anything! The rear axle continued to spin. I pulled the e-brake and jumped out with a flashlight. Hoping no one would come around the bend at speed, and slam into my car. Anyway, I got the car towed to the nearest dealership. Remember, the tune was still active on the car, I can't get a signal in the desert to flash back to stock. I paid the tow truck driver to take my car by my house so I can catch a signal to flash back to stock. An hour+ later, still no signal. It's 4am now.
The following morning I called my SA at BMW, whom I've done a lot of business with in the past. I'm on very good terms with my SA. He allowed me to go to the back of the lot, where my car was stored to get the baby seat out of the car. This time, I caught a signal, and flashed back to stock. I told him 2 stories, the "official" story and the "unofficial" (off the record) story. It's best to be tight and honest with your SA.
I took a loaner car and went to work. My SA called me the following day and stated that there's nothing to worry about, I'd broken my rear driver side axle and it would be covered under warranty. He also stated he was going on vacation the following day and that I would be left in the great care of another SA.
This second SA called me the day the car was to be completed and said that BMW had detected an ECU tune on my car and that the warranty would not cover the repair ($3,100). Of course we all know the risks when modding our cars, so it's understandable. What's not understandable is how they determined the ECU tune to be the culprit of the broken rear axle.
I decided to wait the full week till my real SA was back from vacation. My SA advised me to contact BMW client services to dispute my claim. I had 2 angles to attack this situation from:
1) My car was a BMW NA owned car for the first 9 months of its life (which means it was either a BMW track car or press car), which means the car was likely driven hard in the beginning of its life. Which makes sense since my car has almost every sport and tech option available (original MSRP was around $64k for a 15 335i). But that didn't deter me from buying the car since it was still under factory warranty, and I purchased a solid aftermarket warranty as well.
2) They can't prove the tune broke the rear axle. Several brands (Porsche, Audi, etc...) would have to prove your aftermarket part broke the part in question for them to deny your warranty claim.
Anyway, I lost on both accounts. The BMW field rep determined that everytime he's come across a broken axle, the car had a modified ECU of some type. That was enough for him to deny my claim. My SA agreed that the tune would likely not cause the rear axle to break, so he spoke to the Service Manager. They did offer me a really nice discount to fix the car at $1700.
No matter how you slice it, my car is now flagged for the tune. They said the warranty would still cover non tune related items, even if that's at their own discretion.
Moral of the story, if you play with fire, you're not necessarily going to get burned, but you should know that is a possibility, maybe even a likely possibility if you play with it often. I've owned and modified numerous cars, always knowing this day is possible and likely. It happened to be today... All good! It's my fault, I just want my car back!
Anyway, if you guys ask me, I'll tell you what I think actually caused the rear axle to break, aside from my idiocy of launching the car without using the proper sequence, I'll tell you...

[perryo91]

Damn, interesting read and something everyone needs to be prepared for when tuning their car while under factory warranty. Thanks for the info and keep us updated.

[XxThe_RemedyXx]

Sorry this happened to you. When you flashed back to stock, did you lock the DME or just flash back to your original map leaving the DME unlocked?

[MTWO]

Sucks breaking shit, been there stuck with a tow truck so many times. You seem to have done just a map switch and not a full DME relock flash because if you relocked they wouldn’t see it as it shows then as 100% factory stuff but who knows what other ways they got. Some said they can find traces of tunes if they dig into it in the dash computer as well and other places. Its really as its always been pay to play.

[Bimmertodd88]

I'm guessing you probably didn't flash back to stock and lock dme?

[insanecoder]

You guys actually believe you can flash a BMW DME and reset some flash counter and thereby avoid BMW detection?
I wouldn't put so much faith in it.. they programmed and spec'ed the hardware..
you'd have to understand all of the faculties hardware and software they put in to detect changes and overide / bypass these including perhaps auditing and even real-time communications of such to a central server (I wouldve done that)
If you want a flash tune especially and wish to stay covered in warranty, its best to wait til after your warranty expires
So now the bottom line is the field engineer has the data indicating you had an ECU tune (which you did)
Are you going to risk paying a lawyer to fight and in discovery see what cards they hold?
Yer putting yer faith on that BM3 is undetectable
fact is they could save various metrics which would indicate torque was exceeded and bypassed various built-in BMW safeguards.. safeguards which could be proved to be tampered with via a detected tune flash
good luck

[XxThe_RemedyXx]

Originally Posted by insanecoder

You guys actually believe you can flash a BMW DME and reset some flash counter and thereby avoid BMW detection?
I wouldn't put so much faith in it.. they programmed and spec'ed the hardware..
you'd have to understand all of the faculties hardware and software they put in to detect changes and overide / bypass these including perhaps auditing and even real-time communications of such to a central server (I wouldve done that)
If you want a flash tune especially and wish to stay covered in warranty, its best to wait til after your warranty expires
So now the bottom line is the field engineer has the data indicating you had an ECU tune (which you did)
Are you going to risk paying a lawyer to fight and in discovery see what cards they hold?
Yer putting yer faith on that BM3 is undetectable
fact is they could save various metrics which would indicate torque was exceeded and bypassed various built-in BMW safeguards.. safeguards which could be proved to be tampered with via a detected tune flash
good luck

Good points of course. Just curious of the method he used to flash back to stock. Whether he just flashed back to stock and did NOT lock the DME may give us some critical information.

[TEST DRYVER]

So I did flash back to stock before they checked my car, but did not lock my DME. I honestly didn't know that was an option. Remember, I just got this car and this tune. My biggest mistake, which I realized after flashing back to stock at the Dealership and leaving, is that I should of put the car in Drive. When you have a tune on your car, it pretty much covers up all of your warning lights on the dash after a short period of time. We all know know that most modern cars, especially German cars, are full of sensors. The red flag I threw up was them taking a completely broken car to the shop and not seeing a single malfunction light on the dash. That was a major fk up on my behalf. It's not to say they still wouldn't of detected the tune, but it might of made it less obvious. After flashing back to stock, putting the car in Drive would of lit up the dash like a Christmas tree... That was one of many mistakes I made...

[Mike.]

can't they just see if the DME was flashed? i think it has a flash counter.

[aps]

Originally Posted by Mike.

can't they just see if the DME was flashed? i think it has a flash counter.

latest BM3 tunes freeze the flash counter so this isn't supposed to be an issue. but OP said he didn't lock the DME so the rep was probably very easily able to tell that the DME had been unlocked. wonder how this would have gone if the DME had been relocked.

[XxThe_RemedyXx]

Originally Posted by Anshu

latest BM3 tunes freeze the flash counter so this isn't supposed to be an issue. but OP said he didn't lock the DME so the rep was probably very easily able to tell that the DME had been unlocked. wonder how this would have gone if the DME had been relocked.

I'm wondering this as well.

[insanecoder]

Multibillion dollar company..
relies on a simple flash counter to detect changes to the most important piece of software governing its product

somehow I doubt it
itll at least have some checksum auditing saved in some obscure area or uploaded as part of an update history
and thats not much effort at all

[enjoythemusic]

Very bummed to hear OP, yet nice of BMW to at least discount the repair a bit.

When you mod, you take calculated risks....

[Tribalpinoy911]

This isn't exactly surprising...

[FastF30]

Wow... can't believe the rear axle snapped on a tune... first one I've read on the forums but you said the BMW claims rep said he's seen this before to the point to make it a point.... You said you were messing around with the parameters... was any of that messing around with the boost levels... Just trying to get some insight of what not to mess with...

[jalkster]

Originally Posted by FastF30

Wow... can't believe the rear axle snapped on a tune... first one I've read on the forums but you said the BMW claims rep said he's seen this before to the point to make it a point.... You said you were messing around with the parameters... was any of that messing around with the boost levels... Just trying to get some insight of what not to mess with...

Ive seen a couple 340i's with jb4/meth snap axles

[maxio]

Originally Posted by jalkster

Ive seen a couple 340i's with jb4/meth snap axles

Are the snaps caused by repeated launches of the car?

[FastF30]

Originally Posted by jalkster

Ive seen a couple 340i's with jb4/meth snap axles

I've been on here for 9+months and this is the first reading about it with just a tune anyways...I'd expect this more with a PS2 set-up more than a tune and meth... well this is all good to know and will take note.... but like I said I really never heard of it before, so not gonna really worry about it...

[XutvJet]

Originally Posted by maxio

Are the snaps caused by repeated launches of the car?

Axles typically break from excessive wheel hop. As the tire grabs, spins, hops up and down, and forward and back, the excessive load can snap the axle. Bad wheelhop in a stock powered car can break and axle or differential. If you experience wheel hop, you should immediately get out of the gas. It's no surprise that BMW denied the warranty. Even without a tune, the upgraded IC, the DP, and charge pipe are all evidence (in their eyes) of modifications.

[insanecoder]

you guys DO know launch control puts ALOT of impulse stress on the drivetrain???
this includes the axles ya know
this then after you tune and suddenly load up even more than factory expectations..
I mean wheel hop is even worse cause its more resonance in slippage and bad but lauch control can stressout w/o hop

[wdeerfield]

Originally Posted by insanecoder

Multibillion dollar company..
relies on a simple flash counter to detect changes to the most important piece of software governing its product

somehow I doubt it
itll at least have some checksum auditing saved in some obscure area or uploaded as part of an update history
and thats not much effort at all

Yea right. It's as simple as a checksum or even just a last modified time stamp and potentially even by who or what caused the change. Md5 sum the files and see they were different. He'll. They may even record the history for afr, throttle, boost etc... a simple flash counter seems extremely primitive by today standards.

[IK6SPEED]

Originally Posted by TEST DRYVER

So I did flash back to stock before they checked my car, but did not lock my DME. I honestly didn't know that was an option. Remember, I just got this car and this tune. My biggest mistake, which I realized after flashing back to stock at the Dealership and leaving, is that I should of put the car in Drive. When you have a tune on your car, it pretty much covers up all of your warning lights on the dash after a short period of time. We all know know that most modern cars, especially German cars, are full of sensors. The red flag I threw up was them taking a completely broken car to the shop and not seeing a single malfunction light on the dash. That was a major fk up on my behalf. It's not to say they still wouldn't of detected the tune, but it might of made it less obvious. After flashing back to stock, putting the car in Drive would of lit up the dash like a Christmas tree... That was one of many mistakes I made...

You would do an extremely big favor to the forum if you would talk with the SA you are so tight with and find out in detail how they determined you had a tune.

Or did they just “assume” with all the other parts added?