N54 owners, clean your intake valves!

[Knight F Mohawk]

07 335i, 80K miles
:DISCLAIMER:
Sorry for the rough pictures. My camera struggles with the focus and lack of light/flash.

My fuel mileage was down significantly, and the car didn't feel right under a decent amount of throttle. I decided to clean the intake valves, change the spark plugs, and change the oil/filter for Thanksgiving lol.

Here is what came out:
http://i9.photobucket.com/albums/a92/slovert/STA70428.jpg

A couple before pictures:

This was the "largest" blob of gunk
http://i9.photobucket.com/albums/a92/slovert/STA70408.jpg

I did a quick clean on one side and not the other to get a better grasp of the difference
http://i9.photobucket.com/albums/a92/slovert/STA70407.jpg

Dirty
http://i9.photobucket.com/albums/a92/slovert/STA70413.jpg

http://i9.photobucket.com/albums/a92/slovert/STA70412.jpg

After the first round of cleaning:
http://i9.photobucket.com/albums/a92/slovert/STA70427.jpg

Complete:
http://i9.photobucket.com/albums/a92/slovert/STA70425.jpg


Between the intake runners and valves & spark plugs the car runs LOADS better

-Will

[Parth317]

Wow

[mudd46738]

Great job. How did you do it?

[02325]

welcome to direct injection and poor pcv control.

[thatguyn8]

wait, did you suck up carb cleaner with a shop-vac? I hope that you used some kind of separator...!

[fun2drive]

I plan to do this and install the improved PCV valve as well as using sythetic oil with a higher flash point.
The Castrol BMW synthetic contributes to this issue. There is a guy on the E90 forum with 178K miles on his 335 and he had the valves cleaned at something like 70K miles and switched oils to a higher flash point and now has no issues with more than a 100K miles added.
I do think that is something that does contibute to the build up plus some blow by from the exiting PVC valve.
I have yet to borescope mine at 54K miles but I expect there to be some but not a lot since I am not running the engine hard as some owners are...

[02325]

IMO, also going 15+k miles on an oil change doesn't help the situation any. I think if the intervals were sooner even with the poor ccv/pcv setup, this wouldn't happen as much.

[Knight F Mohawk]

Great job. How did you do it?

I pulled the intake manifold, and cleaned the valves that were closed two at a time. If you play your cards right, four of the 6 cylinder are closed at once.....makes it a lot quicker.

I used a combination of carb cleaner and Berryman's, along with a bronze bristle gun barrel cleaning kit.


welcome to direct injection and poor pcv control.

Yep. I have an OCC on order


wait, did you suck up carb cleaner with a shop-vac? I hope that you used some kind of separator...!

Yes, I did.....No separator. Only thing I used was the coarse filter to keep it from sucking it back up too much. I've done it before with no issues.


I plan to do this and install the improved PCV valve as well as using sythetic oil with a higher flash point.
The Castrol BMW synthetic contributes to this issue. There is a guy on the E90 forum with 178K miles on his 335 and he had the valves cleaned at something like 70K miles and switched oils to a higher flash point and now has no issues with more than a 100K miles added.
I do think that is something that does contibute to the build up plus some blow by from the exiting PVC valve.
I have yet to borescope mine at 54K miles but I expect there to be some but not a lot since I am not running the engine hard as some owners are...
I stopped using Castrol Syntec. I now use Valvoline full synthetic. We'll see how it works.

Mine was pretty seriously gunked up, and I rarely ever enjoy driving my car. It's 99% just daily driving.


IMO, also going 15+k miles on an oil change doesn't help the situation any. I think if the intervals were sooner even with the poor ccv/pcv setup, this wouldn't happen as much.
I thought about that. I'm going to change the oil earlier, and I'm seriously considering changing the filter 1/2 way through the oil interval.


The car literally sounds different now; it runs MUCH better.

-Will

[Ian1973]

What PCV do you purchase instead?

[Knight F Mohawk]

What PCV do you purchase instead?


That, I do not know. I didn't know there was a *better* option. I'm going with an oil catch can.

Anybody have any insight on the PCV?

-Will

[Ian1973]

Stangely I just found the OCC on Burger's site. I will probably purchase this. Do you know if it's a legitimate way to avoid the valve issues or is it more just a snake oil thing?
http://www.burgertuning.com/BMW_335_oil_catch_can.html

[Knight F Mohawk]

Stangely I just found the OCC on Burger's site. I will probably purchase this. Do you know if it's a legitimate way to avoid the valve issues or is it more just a snake oil thing?
http://www.burgertuning.com/BMW_335_oil_catch_can.html

Catch cans aren't a new idea, and they have proved effective many times over. I had to empty the one on my fiance's SRT-4 regularly....better there than the intake though

-Will

[Ian1973]

I'll buy that one then, it may not prevent the coking issue completely, but may help I guess.

[thatguyn8]

Yes, I did.....No separator. Only thing I used was the coarse filter to keep it from sucking it back up too much. I've done it before with no issue.


I guess I'd be concerned about the possibility of the carb cleaner vapors being ignited by the sparks from the shop-vac motor brushes... every now and then you hear about some idiot who tried that with gasoline, lacquer thinner, etc and made a big boom. I'm fairly sure that shop-vacs weren't intended to be used to suck up materials containing VOCs...

As for preventing the issue from recurring, has anyone had any issues w/ dealerships not wanting to work on a car w/ a catch can installed? I think I'm probably due for a walnut blasting although I'll probably put it off until spring, then install a catch can at the same time unless someone talks me out of it. Does the catch can drain back into the crankcase with a check valve, or does it need to be manually drained?

thanks!

[Knight F Mohawk]

I guess I'd be concerned about the possibility of the carb cleaner vapors being ignited by the sparks from the shop-vac motor brushes... every now and then you hear about some idiot who tried that with gasoline, lacquer thinner, etc and made a big boom. I'm fairly sure that shop-vacs weren't intended to be used to suck up materials containing VOCs...

As for preventing the issue from recurring, has anyone had any issues w/ dealerships not wanting to work on a car w/ a catch can installed? I think I'm probably due for a walnut blasting although I'll probably put it off until spring, then install a catch can at the same time unless someone talks me out of it. Does the catch can drain back into the crankcase with a check valve, or does it need to be manually drained?

thanks!

Looking at the design from the online images, I assumed it is a manual drain design

-Will

[fun2drive]

Here is the PCV DIY of the improved one not sold by BMW
http://www.n54tech.com/forums/showpost.php?p=219545&postcount=190

Rob at RBTurbo is selling them.
Here is the entire thread where he posted he built a new one with better sealing under boost.
Still doesn't solve the oil vapor under vacuum however
http://www.n54tech.com/forums/showthread.php?t=15382&page=22

Pretty sure Rob sells these for 45 bucks shipped. I am buying one now and will install this when I do my valves...

[e66man]

OCC may help - but your valves will still have buildup over time. The most likely thing I can recommend to reduce or eliminate the buildup is using 0W-30 German Castrol (Castrol Edge). It has the highest flash points of all 0W-30/40 oils readily available and I've heard keeps the carbon buildup at bay.

I switched to this oil after blasting my valves about 3k miles ago. So I can't say for certain that this is a fix, but I've heard 1-2 other people say it did the trick.

[Sparc_it]

I was having hesitation issues at 23k miles and BMW walnut blasted the car under warranty. Car drives loads better now. Apparently, there was already a significant amount of build up.

[e66man]

I was having hesitation issues at 23k miles and BMW walnut blasted the car under warranty. Car drives loads better now. Apparently, there was already a significant amount of build up.

I'd say you're one of the unlucky ones. Normally codes and driveability issues don't start happening until after 50k miles. But it isn't unheard of that 20k-30k mileage cars are in the shop for a cleaning. Of course it begs the question, will you need it again at 40k-50k miles when most people *might* be doing it for the first time.

[Sparc_it]

I'd say you're one of the unlucky ones. Normally codes and driveability issues don't start happening until after 50k miles. But it isn't unheard of that 20k-30k mileage cars are in the shop for a cleaning. Of course it begs the question, will you need it again at 40k-50k miles when most people *might* be doing it for the first time.

Yea, but by that time, I don't plan on having this car anymore and will have moved on to something else.