[MteK]

Recently picked up an 08 135i. My mechanic has been talking to me for some time about the major carbon issues that the DI engines are having. He is a well regarded former BMW tech who opened up his own shop. According to him this is becoming a big issue in the BMW tech circles as more of these cars hit the roads.

He recently picked up a BG Via Induction cleaning system specifically to address the carbon issue. I picked up the 135 with around 44K mi and after seeing Mr.5’s post on carbon build up decided to try and clean out the guts before beginning any modding.

We decided on a 3 step process.
1 – Bore scope the intake valves for condition
2 – Run BG cleaning service
3 - Bore scope afterwards to determine effectiveness

Car Specs: CPO 08 135i with 44K miles. Never modified. Dealer serviced. No issues.
The following comments are from my mechanic.


IMG's 1,2 shows Steve Cardelli of Cardelli Motorsports scoping an intake valve in cylinders 3 and 4. What you are looking at are 2 shots of the carboned up valve stems. The actual valve end is towards the upper left of the screen. The stem is going diagonal from upper left to bottom right. Pretty nasty. These shots were taken before the BG intake cleaning service.




IMG 3 shows the BG intake cleaning service in action. What I have done here is I had injected the BG solution into the intake tracked both at idle at 2500RPM. Then after using up the solution in the injection cylinder, I then filled it with water and had injected at least half of it at around 2500 RPM. After the service, I took the vehicle on a road test and found the engine to feel a little more brisk and the idle quality had improved, especially when starting the vehicle the very next morning after the service.




IMG 4 shows an intake valve of cylinder #4 after the intake service. You can actually notice a slight difference compared to the other photo taken before the intake service. It actually looks a little less sooty, but there is still hard carbon buildup on the stem.




Decided to remove the intake manifold.


IMG's 5 and 6 shows the disaster in cylinders 4 and 5. Nasty!




Continued-

[MteK]

IMG 8 shows one of the copper gun brushes used to help scrub the carbon off the valves. I had bent the tip to help in scrubbing the back end of the valve stems.



IMG's 9-13 shows the cleaning process at work. I moved each of the cylinders to TDC then filled the intake ports with BG intake cleaner up to the valve guides, let them soak in the solution for at least ½ hr, then scrub the heck out of the valve with the pistol brushes. Cylinders 4, 5 and 6 needed to be soaked twice and the hardened carbon scraped off using a couple of dental picks. Then once scrubed down, the valve intake ports were washed out with brake cleaner and compressed air.







IMG's 14,15 show the results.





Once the car was put back together I noticed the idle was much smoother. There were no “hiccups” and there was a significant increase in power through-out the entire RPM range but particularly up top.

To prevent this from happening again we decided on routing BSG service every 10K. I’ll crack it back open in about 30K to see how it’s held up.

If anyone local is interested in the service my Tech’s Name is John with Alternative BMW Service (ABS) in San Mateo.

[Elie335i]

awesome thread, THAT'S HELL OF CARBON AT 44k miles only, Mr.5 did the valves clean, and he's almost at 100k miles. His valves looked much more better then yours.

[KyLu II]

Originally Posted by Elie335i

awesome thread, THAT'S HELL OF CARBON AT 44k miles only, Mr.5 did the valves clean, and he's almost at 100k miles. His valves looked much more better then yours.

Keep in mind that mr 5 has meth injection...

[MteK]

Originally Posted by Elie335i

awesome thread, THAT'S HELL OF CARBON AT 44k miles only, Mr.5 did the valves clean, and he's almost at 100k miles. His valves looked much more better then yours.

This car had no mods that might help, no meth, no catch can, nothing.

[Elie335i]

yup right..

[Rotorocious]

How did you manually move it to TDC? Socket on the crank?
I'd like to try this.

[vasillalov]

Yep, get used to it guys. This is issue is not from to day or yesterday. The RS4 guys have their engine heads taken out and rebuilt every 30-40K miles because of this.

We should be glad that we have an engine which allows us to clean it some of this crud ourselves.

[chili36]

Originally Posted by Rotorocious

How did you manually move it to TDC? Socket on the crank?
I'd like to try this.

+1

[Clap135]

Thats is pretty nasty, however I don't know why your mech sprayed that stuff through the intake, he should have sprayed it directly into the throttle body or the chargepipe/cold pipe connection. Not sure I would spray that stuff onto the turbos....

[Rotorocious]

Also, any replaceable parts needed when pulling the intake?

[MteK]

Originally Posted by Clap135

Thats is pretty nasty, however I don't know why your mech sprayed that stuff through the intake, he should have sprayed it directly into the throttle body or the chargepipe/cold pipe connection. Not sure I would spray that stuff onto the turbos....

That crud coats your fmic and intake manifold also.


I'll check with him on how to turn the crank + replacement parts

Also forgot to add changed oil afterwards

[Mr. 5]

Thanks a lot for posting this!
Your valves look awesome after the cleaning and you should definitely pick up some power.

This should show people how bad it could get without meth or a catch can.

[zsapphire7]

if you dont mind me asking, how much is it to get a nice scrubbing ? Im at about 43k and i think ill need to get this done as well...

[dzenno]

Wow that's gross man, I'm doing my scrubbing this Saturday

[NiVeDh]

Good stuff.

[Krozi]

Man, you did work lol

[Tzu]

How did you vacuum out the residue? What about the crap that falls into the cylinder because you couldn't possibly have vacuumed it all out.

[TwinSnails]

Originally Posted by zsapphire7

if you dont mind me asking, how much is it to get a nice scrubbing ? Im at about 43k and i think ill need to get this done as well...

Interested to know approx cost as well.. Im local. Post here or PM me. Thanks.

[MteK]

Originally Posted by Tzu

How did you vacuum out the residue? What about the crap that falls into the cylinder because you couldn't possibly have vacuumed it all out.

Setting the cylinder at TDC seals the valves, use compressed air to blow it out.

Originally Posted by TwinSnails

Interested to know approx cost as well.. Im local. Post here or PM me. Thanks.

You can call John at (650) 393-5502

[Presidio335xi]

do you use cheap gas? or is this more the result of oil contamination?

[Rotorocious]

Originally Posted by Presidio335xi

do you use cheap gas? or is this more the result of oil contamination?

Gas doesn't even touch these valves.