[Owen81]

Just thought I would share, I recently bought a 335d with 117k kms on it. I knew it would have CBU but didn't think it would be too severe since I have been getting great mileage with it.

Well I had to pull my intake manifold when changing the glow plug control module so I took some pics:

EGR


Manifold intake ports


Manifold swirl ports


Head swirl ports


Head intake ports


Looks like they cleaned the intake ports, but didn't bother to clean the swirl ports or the intake manifold at all.....

I can get the manifold cleaned, but I plan on installing meth injection in the near future, would it be worth cleaning the swirl ports on the head or just wait for the meth to do its magic?

I would have to buy all of the blasting tools...

[glitdi]

how many miles since the intake was cleaned... its not far from feasible that that is new carbon build up, it likes to stick to plastic. egr looks cleaned, it builds up quick due to the 90 degree angle the exhaust has to navigate.
I would take the intake and run to lordco, or any engine shop and have the intake hot dipped, (ultrasonically cleaned) its about $50 bucks and a couple of days, and block off your egr.
Or spend $400 ish for water meth...

[Owen81]

I'm not sure when it was cleaned, I bought the car used without records.
The swirl ports on the head have significant build up while the intake ports are very clean, which makes me think the buildup isn't new?

I have already blocked the EGR ports, will probably get the manifold cleaned when I do my down pipe install and leave the rest for the water/meth down the road.

[Hoooper]

I would clean it. Meth does a lot more work on the rectangular ports unless you plan to install a small nozzle that will inject at low boost.

[Puerto Rican 335d]

damn thats nasty my car is coming up on 60 k which last 11k have been w/o the gizmos wonder how it would look like. I plan to post pics when we do it ok guys

[Chief Orman]

I know this has been posted many times before but is there a generic code that one can use to coerce the dealership to inspect one's car for CBU? Every time I complain about mileage or some other issue related to CBU I get the "you're on your own" song and dance from the SA.

[glitdi]

Engine smoothness is a good one, any maf related ones is a good indication. Try another dealership if you aren't getting the outcome you want. I have had to "educate" dealerships on there own vehicles and what I wanted done on numerous occasions. Go in prepared, bring the service bulletin with you and be nice and be willing to tell some stories.

[grant123]

i'm getting lumpy idle on cold startups which i suspect is CBU, i plan on getting my dealer to investigate. Whilst i have the extended warrenty still available it would be good for the work to be carried out

[Lexx.md]

Same on my diesel, have cleaned it, but still have obd codes

[Chief Orman]

Originally Posted by glitdi

Engine smoothness is a good one, any maf related ones is a good indication. Try another dealership if you aren't getting the outcome you want. I have had to "educate" dealerships on there own vehicles and what I wanted done on numerous occasions. Go in prepared, bring the service bulletin with you and be nice and be willing to tell some stories.

Good idea...didn't occur to me to bring in the service bulletin

[glitdi]

Originally Posted by Lexx.md

Same on my diesel, have cleaned it, but still have obd codes

Hope I am not beating a dead horse, I dont get on this site nearly enough.
However I must share with you my experience, after cleaning the cbu I still threw codes on a regular basis and would limp from time to time.
I booked it into the dealership to have the injector adaptation values reset and the software updated to the newest version.
Fixed this issue instantly!
On that note it took me 4 days of walking the dealership through exactly what I wanted, having them do something completely different advising me against it and saying it would damage my engine.
After explaining to the service rep that I knew more about German Diesels than he did they did the flash reluctantly... Fixed the problem instantly car drove fine... Free free free of charge due to certain complication and incompetence on the dealerships side... Exact words were we must look like idiots to you!
Responded with no not at all and its good for you to question what your customers say...in most instances...not this one!
Moral of the story is that it fixed my issues with the car, (might not fix your issues but we have similar symptoms and it fixed mine... But be aware I am not there to diagnose your car in person, I assume no responsibility!)
Moral 2 know what you are talking about!
Moral 3 Play nice! I had many opportunities to flip out! they had my car for a week for a 2hr program... Took days of re iterating the story to the service rep, manager, tech etc before I got what I wanted and it didnt cost me a dime due to my good nature...
Hope this helps.

[Chief Orman]

Originally Posted by glitdi

Hope I am not beating a dead horse, I dont get on this site nearly enough.
However I must share with you my experience, after cleaning the cbu I still threw codes on a regular basis and would limp from time to time.
I booked it into the dealership to have the injector adaptation values reset and the software updated to the newest version.
Fixed this issue instantly!
On that note it took me 4 days of walking the dealership through exactly what I wanted, having them do something completely different advising me against it and saying it would damage my engine.
After explaining to the service rep that I knew more about German Diesels than he did they did the flash reluctantly... Fixed the problem instantly car drove fine... Free free free of charge due to certain complication and incompetence on the dealerships side... Exact words were we must look like idiots to you!
Responded with no not at all and its good for you to question what your customers say...in most instances...not this one!
Moral of the story is that it fixed my issues with the car, (might not fix your issues but we have similar symptoms and it fixed mine... But be aware I am not there to diagnose your car in person, I assume no responsibility!)
Moral 2 know what you are talking about!
Moral 3 Play nice! I had many opportunities to flip out! they had my car for a week for a 2hr program... Took days of re iterating the story to the service rep, manager, tech etc before I got what I wanted and it didnt cost me a dime due to my good nature...
Hope this helps.

Good advice. Part of challenge is figuring out what needs to be updated from a software perspective and what doesn't. When I had my transmission issues it was only at that point that anyone thought to download the latest transmission software.

It would be really helpful if someone in the know could construct a list as it relates to the car's software to make sure absolutely everything is up to date. Which is to say, being able to give the SA a list of items and demanding that they demonstrate to you that all the systems on the car are in fact up to date.

As I sit here and think about it I become progressively more pissed given that I asked the SA on at least five separate occasions over the last year tom confirm my car had all the necessary updates when clearly it never got the required transmission update. I sometimes wonder if they even know that they are looking it when they pull up various computer screens while I am sitting in the dealership.

[glitdi]

Its a time issue with the techs...Nowadays in N.A. Most techs are on book time, the manufacturer pays the dealership for warranty work. They determine it takes 4.5 hrs for a job, in the factory with all the information known on the repair, symptoms etc.... For a tech to do it properly can be double that, the art of diagnosing a repair is simply lost. Dealerships throw parts at a car to keep under the allowed time for a repair, wasting a ton of parts and missing other issues in the process... How many people have had injectors replaced for no apparent reason?
So when the tech plugs into the car they pull up codes, what the oem wants them to do and they get to work, not uncommon to not update the software unless they think its causing an issue... I had to ask for the tech records when my car went in last to verify the software was updated to the newest version....