Hey Gang,
I just pulled the intake on my 2007 MCS with ~46200 miles.
Attached are blury pics of what I found. What is evident is that I cannot see how this poor engine was breathing at all!!
Tommorow I plan-on soaking the intakes in with carb cleaner and scrapping clean (as much as possible).
My question is: With so much crap on the valves, it is difficult to see which valves are open/closed.
Is there another way (other than visual) to tell when the intakes are closed on a particular cylinder?
Thanks
Lee

 

You're right the pictures are blurry but I can see the build up. I have about the same number of miles, interested to know how it works out.
There was something on here that mentioned using a wood dowel stuck down the spark plug hole to find TDC. With the piston at the top, the valves should be closed.
Good luck!

 

Thanks Grege for the idea.
BTW, anyone know the torque of the intake manifold nuts?

 

Hey Gang,
Just finished the intake valve cleaning on my 2007 MCS.
It was approx:
-3 hours to remove the intake manifold
-10.5 hours to clean the valves
-1 hour to install the intake manifold and test
As the 'before' pics (above) will atest, the valves/intake of the head were pretty caked-up with gooey carbon. In the 2nd and 3rd cylinder intakes, it was difficult to tell where the valve ended and the carbon build-up (from the rear of the intake passage) started!! Really nasty.

But, the work was worth the effort. Now when I am accelerating hard in corners, the steering wheel (once again) suffers from extreme torque-steer (me likes! ) and the acceleration is definetly more 'head-snapping'.
Next move is to install a BSC OCC which I hope will arrive by next Tues/Wed.

 

The improvement looks great! Glad you found improvement and hope to do the same in a few months.
The total time invested was about 15 hours from what you posted. What tools, chemicals did you use?
Thanks

 

This makes me want to sell the Mini

 

Hey Greg,
Below are the tools that I used. Hope it helps!

 

Woa those were pretty bad. Good for you doing it yourself and learnin more about your MINI!

 

Thanks Surfin for the picture. The labels for the tools are terrific. Thanks again.
Glad your results were great!

 

Wow, ordered my OCC for the new coupe today after seeing this.

 

So is the carbon problem much worse in S models? My 2008 has over 75k on it and with not so much as a seafoam treatment it's still going strong with no loss of power compared to my 2011 r55.

 

Is this carbon build up mostly a problem for cars that have been driven hard?

I have a 2007 Mini Cooper s with 34,000 miles on it, I am not flooring it constantly and I doubt the previous owner did.

Should I be concerned about this?

 

The carbon problem is on the S models only as they are the only direct injected engine from Mini. The standard Cooper is port injected.

I don't believe how you drive the car affects the build up or not. Hours of trolling this forum shows that just about everyone has carbon problems if you have an S...

Those who don't have the carbon problem, simply haven't opened up their intake yet.

 

Prett sure they're all direct injected, turbo or not.

 

I'm just going off what I've seen on this forum, but I do not actually know for fact (aka I haven't been under the hood of a justa).

https://www.northamericanmotoring.co...injection.html

That and I'm not quite sure of the year to year changes but I'm would still place my money on only the cooper s being DI

 

From what I have read, Audi direct injection engines suffer from the same issue.
My neighbor is a SA for MINI. He tells me that there is a SW update (came-out last ~Nov) to help addressthe carbon build-up issue. Adjusts the timing and does not effect the performance.
As a follow-up; when I first fired-up my MCS after doing the valve cleaning, there was a stumble at idle, but, then it evened-out. I took it on a 7 mile test drive with no probs.
Then, I left it sitting for 2 days. When I started it yesterday, it had a yellow engine light. I disconneced the battery overnight and restarted this morning and still have the yellow engine light. I am trying my best not to drive it until I install the OCC, but, may cruize to Autozone to see what the code is.

 

From my experience around the garage and working on engines when I was younger, this build is hard to avoid and on a turbo car the oil gets thrown back into the intake because of dumb emission laws. A catch can will help some. Also driving the car slowly and not letting the engine get hot and cycle through its entire rev range will also cause premature build up.

So in my opinion the best way to keep this build up is to run good clean gas, let the engine warm up proper and get on the gas and put the engine on load and let the engine run at various rpms. Besides running around town at 5,000 rpm in 2nd gear is just fun

My friends 95 NSX had bad proformance and couldn't pass smog because it sat so much. After a tank of gas and hard driving the car passed emissions.

But as with everything you read on the net, take it as a grain of salt.