[335i 07]

Originally Posted by samchoi604

The borescope method is an extremely good idea 335i_07. Sorry for the noob question though, where is the throttle body clip you mentioned? Do I need to remove the air intake box?

This is the clip. Just take your airbox off pull clip up and undo. If you follow the pipe you disconnected you will see a bolt. Undo that bolt for more play to insert borescope.

[samchoi604]

Originally Posted by 335i 07

This is the clip. Just take your airbox off pull clip up and undo. If you follow the pipe you disconnected you will see a bolt. Undo that bolt for more play to insert borescope.

Thank you!!! Going to try and rent a borescope, if not possible, then I'll buy one from Home Depot then return it after I'm done.

[Bamaben]

Dealer told me they blast the carbon with walnut shavings. I've seen this done on American Restoration. Dealer said the buildup is worse on autos than manuals due to manuals usually rev higher and this prevents buildup.

[335i 07]

Originally Posted by Bamaben

Dealer told me they blast the carbon with walnut shavings. I've seen this done on American Restoration. Dealer said the buildup is worse on autos than manuals due to manuals usually rev higher and this prevents buildup.

Blasting with walnut shells=$600+
Cleaning with gun kit and stuff=$75

If under warranty some dealerships will do this for free. Its about a 50/50 chance. One person on here complained of rough idle and they hooked him up with a cleaning. Always worth a try if you have miles racked up. I don't see how manuals wouldn't have the same build up if not worse. Manuals tend to boost more frequently causing more blow by circulated through your PVC into the intake. Correct me if I'm wrong.

[galahad05]

Just ordered myself a video borescope for eighty bucks shipped. Harbor Freight is the awesome.

Their more expensive stuff is good quality (and relatively cheap).

[DASHOCKER]

This borescope can come in handy on dates.. I must order one.

[bumere90]

This stuff works the best
http://cgi.ebay.com/ebaymotors/ws/eB...84.m1423.l2649

[CALWATERBOY]

Originally Posted by 335i 07

Sea Foam will not work well through intake line! The carbon was rock solid and I had to soak and scrub 3 times. I used three different brass gun brushes. I used the same active ingredient as sea foam for the soaking phase. Others used sea foam through vacuum line and pulled intake manifold to inspect with no or very little results.

How thick was the buildup?

Usually happens in modded engines....maybe yours was w/prev owner.

Stock Audis had a problem with this; BMW's PCV separator in the head does an excellent job preventing this issue, unless specs are exceeded.

Methanol injection reputed to prevent the problem. Don't know if will remediate! Lil' help?

[Edward]

This really sucks about DI engines. Most performance engines are DI or headed there and they are all somewhat susceptible to this power robbing issue.

I have no mods and drive my car hard on acceleration but don't necessarily redline it much because the N54's power level sucks at 6-7k rpms. I use only Shell V power but that doesn't matter much at all since none of the detergents ever pass over the intake valves. Anything else I can do to prevent this type of buildup?

I have to believe that not every N52 or N54/N55 engine that hits 75k miles will look the same the ports and valves right?

[Maestro]

I wonder if you can get the dealer to do this under the extended maintenance program. to me this looks like normal maintenance you have to do on the engine, not different than flushing the brake fluid or coolant. I got 53K on my 07 and wonder how bad it is at this point.

[tunachris]

I asked about valve cleaning while I was getting some work done on my car. It is a 2010 335i, 6MT. Car was at HP Autowerks getting the differential fluid changed. The tech told me that it was a good idea to do it every 25,000 miles.

Since I had about 26,000 on the car, I have decided to wait until the next covered oil change. I do an oil change every 7,500 miles, and I did the plugs at 25,000. I did pick up a can of BG44K and used it a couple of weeks back. Still the DI issue as stated means nothing going through the intake valves.

[335i 07]

Originally Posted by Edward

This really sucks about DI engines. Most performance engines are DI or headed there and they are all somewhat susceptible to this power robbing issue.

I have no mods and drive my car hard on acceleration but don't necessarily redline it much because the N54's power level sucks at 6-7k rpms. I use only Shell V power but that doesn't matter much at all since none of the detergents ever pass over the intake valves. Anything else I can do to prevent this type of buildup?

I have to believe that not every N52 or N54/N55 engine that hits 75k miles will look the same the ports and valves right?

Wrong, plenty of N54 Valve cleaning pictures on internet that looks just as bad with half the miles. Remember my car was a lease that was driven normal without a tune. I only put 10,000 miles on the car with the tune. Personally I think N54s with or with out a tune will look very similar. Look at Mr. 5s valve cleaning. His are pretty bad and he sprays Meth that aids in the prevention and cleaning of build up.

[Bamaben]

Originally Posted by 335i 07

Blasting with walnut shells=$600+
Cleaning with gun kit and stuff=$75

If under warranty some dealerships will do this for free. Its about a 50/50 chance. One person on here complained of rough idle and they hooked him up with a cleaning. Always worth a try if you have miles racked up. I don't see how manuals wouldn't have the same build up if not worse. Manuals tend to boost more frequently causing more blow by circulated through your PVC into the intake. Correct me if I'm wrong.

the dealer foreman's statement was mainly pointing out that common auto driver wouldn't drive as hard and hold revs as long and burn off the blowby as most MT cars would. I would thing that the more you boost and for longer periods would burn off more blowby than a quick boost and then a drop in revs due to shifts by an auto..

[SteVTEC]

Originally Posted by Edward

This really sucks about DI engines. Most performance engines are DI or headed there and they are all somewhat susceptible to this power robbing issue.

I have no mods and drive my car hard on acceleration but don't necessarily redline it much because the N54's power level sucks at 6-7k rpms. I use only Shell V power but that doesn't matter much at all since none of the detergents ever pass over the intake valves. Anything else I can do to prevent this type of buildup?

I have to believe that not every N52 or N54/N55 engine that hits 75k miles will look the same the ports and valves right?

The N52 ought to be spic n' span because it's port-injected.

[JoosyJoos]

One concern that I have is that by brushing the surface clean of all that carbon build up you're creating micro scratches that are more susceptible to accumulating carbon in the future. You're giving it a slightly rougher surface to stick to in the future. Not sure how that could be prevented though...

[Edward]

Originally Posted by SteVTEC

The N52 ought to be spic n' span because it's port-injected.

STILL? how old is the technology in that engine? I knew it was similar to the M54 or whatever they put in the 330ci etc in the E46 days but man, that's weak if it's still in essence that same engine.

[galahad05]

Originally Posted by JoosyJoos

One concern that I have is that by brushing the surface clean of all that carbon build up you're creating micro scratches that are more susceptible to accumulating carbon in the future. You're giving it a slightly rougher surface to stick to in the future. Not sure how that could be prevented though...

High-temp teflon coating?

[JoosyJoos]

Originally Posted by Edward

STILL? how old is the technology in that engine? I knew it was similar to the M54 or whatever they put in the 330ci etc in the E46 days but man, that's weak if it's still in essence that same engine.

How is that "weak"? That's pretty much the way ever BMW engine has ever been conceived.

M50 --> M54 --> N52
S50 --> S54

They're all just engineered to be one improvement on top of another. Heck, look at the Porsche block... it hasn't changed in 40+ years (until the new 991) and its worked out fine.

FWIW the N52 has the lowest weight per horsepower of any 6 cylinder engine and still makes use of VANOS and Valvetronic. Pretty impressive you ask me... and the Wards engine of the year voters agree (2006-2007).

If the new 4 cylinder gets the same accolades I'd be impressed.

[335i 07]

Originally Posted by CALWATERBOY

Mentioning catch can, assume these are intake valves. Seafoam no help there.

Would you say deposit was more than paper thin?

I'd say the build up averaged about 5 sheets of paper thick. In some areas more.

[David1]

Originally Posted by JoosyJoos

One concern that I have is that by brushing the surface clean of all that carbon build up you're creating micro scratches that are more susceptible to accumulating carbon in the future. You're giving it a slightly rougher surface to stick to in the future. Not sure how that could be prevented though...

Makes no difference.

[mjollnir19]

that camera is awesome... i gotta get one...

[Wes335XI]

Originally Posted by 335i 07

I don't see how manuals wouldn't have the same build up if not worse. Manuals tend to boost more frequently causing more blow by circulated through your PVC into the intake. Correct me if I'm wrong.

^This +1. I honestly do not think it would matter if it's an automatic or a manual. I would agree that a manual would be worse, more spirited driving and more boost as you would have more control over when to shift. That's the fun part of a manual.

It's a tiwn turbo charged car, the key being it is a turbo. All turbo charged cars will experience blow by at some point in their life time. Google "oil blow by" and there are several good articles that explain it. My STi had so much gunk built up in the lines it was beginning to hurt my performance, as it got older more and more oil was found in the intake system. An air oil separator solved this issue and showed an increase in performance, clean exhaust again, and a decrease in oil consumption.

So everything here is normal, blow by is something you will have to deal with. I'm new and curious if any of you have an oil catch can or if they even make an AOS for the 335? The AOS is really nice as most are maintenance free. As I start to mod it it is something I hope to invest in. The one for my STi was worth every penny.

Thanks,
-Wes