[AustinMsport]

Almost 59K miles now..........no CBU yet.

[mefferso]

Originally Posted by kbturbo

Just dropped mine off at the dealership tonight. Had an insufficient egr flow detected code. Still under cpo. Light came on at 50,300 miles. After driving the 2015 X1 loaner car home, I'll be happy to have mine back

Are you getting cleaned for CBU?

[AustinMsport]

Originally Posted by Austin335D

Almost 59K miles now..........no CBU yet.

Performed the test. No stumble at all at 59K. Weird.

[AzureHaze]

Close to 51k. No signs of CBU.

[SLH350]

I'm at 63k with no issues yet, BUT my CPO coverage runs out in 2 months. How much is a carbon cleaning going to run me out of warranty? Almost wish I'd just pop an SES right now, considering maybe trying to convince an SA to have a look before the warranty runs out.

[remlemasi]

HA! So much for me claiming no CBU!

Started the car this evening and it immediately went into limp mode with SES light.

Funny thing is limp mode went away after driving for a few minutes. Came back after I turned off the engine to refuel and restarted it, but went away again after a few minutes of driving. Didn't actually feel like power was reduced much for being limp mode.

Got home and found three codes. From iViNi BMWhat report:

- Fault: Air flow meter signal / Air mass meter / Air mass sensor
- Code: BMW 4BC2

- Fault: Intake air temperature sensor / Supply air temperature sensor
- Code: BMW 4831

- Fault: intake air temperature sensor / intake air mass air signal / Input air temperature sensor (reference signal for air mass sensor) / inlet air temperature sensor reference signal for air mass meter
- Code: BMW 4BC6


I'll bring her in to the local dealer soon. Are we still seeing any cases of dealer or BMWNA refusing to cover CBU or is it a slam dunk at this point? Of course, I'm assuming for now that the diagnostic will come back as CBU.

[Mik325tds]

Uh. With those codes alone you're probably just in for a new MAF sensor if they don't just clear the codes and send you home (suspicion of just disconnecting the MAF).
For a CBU diagnosis I think you'd need at least one of the following in addition to the MAF fault:
4595 rough controller Cylinder 6
459B rough controller Cylinder 5
4592 rough controller Cylinder 4
4596 rough controller Cylinder 3
4593 rough controller Cylinder 2
459C rough controller Cylinder 1
injector adaption values

So, I wouldn't expect a slam dunk at this point.

[remlemasi]

Originally Posted by Mik325tds

Uh. With those codes alone you're probably just in for a new MAF sensor if they don't just clear the codes and send you home (suspicion of just disconnecting the MAF).
For a CBU diagnosis I think you'd need at least one of the following in addition to the MAF fault:
4595 rough controller Cylinder 6
459B rough controller Cylinder 5
4592 rough controller Cylinder 4
4596 rough controller Cylinder 3
4593 rough controller Cylinder 2
459C rough controller Cylinder 1
injector adaption values

So, I wouldn't expect a slam dunk at this point.

Gotcha. So maybe I'm a little too excited about this CBU thing...

I'll let you all know what the outcome is. I'm secretly wishing for CBU in the next 25K miles while I'm still under CPO.

[eagerlee]

I read the how-to on the 5-series forum and none of the steps look too tough, except the actual cleaning is messy but do-able. I really don't think we have to drive in fear of the Carbon Build Up in the Exhaust Gas Recycle valve, intake manifold or associated plumbing. It appears that any reputable dealer will cover it under warranty and if no warranty, well then jump in and get your gloves dirty and fix it yourself. Read this procedure and see if you agree: doing a dis-assembly and inspection, cleaning if necessary, is less work and less risk than modifying the plumbing to mitigate the build up. Thank you very much 9mmkungfu and ANZAFIN.

Originally Posted by 9mmkungfu

If you guys want to check for carbon build up, read this thread here:

http://5series.net/forums/diy-do-you...-engine-53457/

[Hoooper]

that procedure doesnt include cleaning the intake ports in the head which is by far the most difficult, involving, and probably beneficial step

[ingenieur]

Originally Posted by Mik325tds

Uh. With those codes alone you're probably just in for a new MAF sensor if they don't just clear the codes and send you home (suspicion of just disconnecting the MAF).
For a CBU diagnosis I think you'd need at least one of the following in addition to the MAF fault:
4595 rough controller Cylinder 6
459B rough controller Cylinder 5
4592 rough controller Cylinder 4
4596 rough controller Cylinder 3
4593 rough controller Cylinder 2
459C rough controller Cylinder 1
injector adaption values

So, I wouldn't expect a slam dunk at this point.

And mainly 3FF1 - air mass too low

[thefriar]

I'm not sure if I'm CBU or what, but I'm guessing my past 100 days of:

DEF Replacement Oct '14
Throttle Body Replacement Dec '14
New Battery Jan '15
New FRMS/Control Unit Jan '15

Won't unlock or start again as of this evening (5th time since Nov 29th).

Mileage is stable as is performance. At this point if its DDE and CBU, I'll be happy... they'd said the last fix for the ignition/FRMS control unit full replacement with new keys (got it back yesterday) should fix things.

I still think there might just be a fuse, but they're only fixing whatever codes get thrown vs. checking what the problems might be.

I'm at 63.5k miles... '11 with inservice Sept 11, bought it at July 12. Have done the additives.

Will probably be getting rid of it now given its been in the shop more than in my possession over past 2 months.

[remlemasi]

Originally Posted by remlemasi

Gotcha. So maybe I'm a little too excited about this CBU thing...

I'll let you all know what the outcome is. I'm secretly wishing for CBU in the next 25K miles while I'm still under CPO.

Looks like my wish came true. Rough idle started this morning and efficiency and power seem to be down a little.

No codes yet and I know they can't work on it until codes are thrown, but should I go to dealer now so they can start documenting the symptoms?