so for all you guys that have run into this problem, what are your driving styles like?

i used to baby my car, rarely gassing it, but i've been told that regularly revving the engine helps avoid this...

 

Walnut shell blasting performed at 39k miles. Now I'm at 47k miles. In the 8k miles after the valve cleaning I had been running meth via Aquamist HFS-4, so I'm a happy camper.

No issues to date since. I drive aggressive and I track, so no babying the MINI here.

 

This isn't going to help. That idea is from the old days, when cylinders of carbureted cars would build up carbon, and getting the engines really hot would burn some of that carbon off. This build-up is outside of the cylinders, on the intake valves and runners.

 

What!!! You mean now I'm going to have to drive aggressively just for fun?

 

'09 MCS
25K miles
Engine light came on, brought it to Universal City Mini.
Repaired at no charge because still under manufacturer warranty.

 

so, just to confirm, that harbor freight 15lb portable soda blaster is good for cleaning the carbon on the intake valves?

As in, I can use this blaster and a vacuum to suck out the media instead of manually cleaning with a brush, right?

 

Check out this thread.

 

thanks, scooter! That was extremely helpful!

 

2008 MiniS dx'd with carbon buildup at 27k miles; engine was "missing" before the cleanup and now runs fine; question: when shifting, I have skipped gears i.e., I'll shift from 3rd to 5th or 4th to 6th when I'm going fast enough to do so...never noticed any lagging, but could this have contributed to the carbon issue?

 

i've had the check engine light multiple times for various reasons, but mostly because of buildup. i have a 2010 S which now has 52,000 miles. most recent buildup problem was fixed yesterday for more than $600. i would have to check my records to be sure, but i think this was the third time for the exact same problem, though it was the first time i actually had to pay for it. apparently, the extended warranty doesn't cover this, even though it appears to be a vehicle design defect.

i've never put anything but 93 octane in the car, and i routinely add a bottle of techron. this has not fixed the problem, though that's what they tell me to do every time i bring it in for the same issue. this time, they're recommending crud b gone, so i'll do that.

i love the car, but i've never had this many issues with a brand new vehicle right out of the gate. when this happens again, i'm contacting Mini, because they need to make this right.

 

Nice handle! Private shops such as Helix can do it for much less. We charge $350 for the job, utilizing the factory walnut shell cleaning machine.

 

thanks!

i'll certainly look into other options. i generally keep my cars for a very long time, and had planned to do so with the S, as well. however, exorbitant maintenance costs might keep me from doing that. i'm cautiously optimistic, though, because i really like the car.

 

I ended up taking mine to the MINI house since mechanics nearby either couldnt do it, or werent giving much of a price break. I also tried to take it apart and manually clean it like some of the other threads mentioned, NOT easy as it seems. Ended up $768.00 :(

 

Motoring Magic in Thousand Oaks(north of Los Angeles) does it for about $400

 

07 MCS - 90k miles - $400 for the cleaning.

 

07 Mini S, 75,000mi, $500 for walnut shell cleaning.

 

I have been a Mini supporter since we bought our first Mini's in 2009. I traded in my 09 MCS on a 2012 JCW Coupe. We really like the cars. But I am starting to be a guy who has Mini's but is now starting to make plans to off em.

I'm starting to have that "I've been taken" feeling. My wife's car has about 56000 miles on it now. She drives 48 miles to work round trip 4 days per week. This is freeway driving at 60 to 65 mph. So her car gets warm. We put the gas treatment in every 3000 miles, change the oil every 7500 miles, only Chevron top tier premium fuel and we drive them. Drive them hard.

Trust me it makes no difference. You can do all you want but it will not stop the problem. She has now had the top end of the car done due to timing chain issue, replaced the turbo pipes, had the walnut cleaning due to CEL misfires caused from carbon buildup 11,000 miles ago, and had to have it done again last week. The car is out of factory warranty but does have the extended bumper to bumper and extended maintenance warranties. Neither which cover the carbon problem. The dealer was kind enough to comp the cleaning, the dealership paid 66% of the bill and Mini paid the balance. I was told the next time I would have to pay $350. I guess since I have spent about 100K with the dealership they thought it a decent thing to do. It was.

It was kind of demeaning to my wife. The service guys says, this is your wife's car right, I said yes , he said well she needs to drive it harder. Trust me my wife's drives her car hard enough. That has nothing to do with it. It's a design defect plain and simple.

Anyway I'm not going to go on and on. It's just apparent to me that the Mini is overpriced for what it is and I guess it's my fault for not doing my due diligence. I have to take responsibility for that.

So were to the point where were just going to drive the crap out of them and trade em off. It's good both cars are paid for so that isn't an issue. We'll keep my wife's car till the warranty is up. 100K or 6 years. Mine is a different issue. I'm not going to buy the extended warranty on mine. WAYYYYYY to expensive. So I'm going to trade it in at 4 yrs or 50K. Someone will get a good ride. We take good care of our cars.

Anyway the point is these cars are way expensive for what they are. Sure they handle great and all that, I agree, fun as all get out. But the cost to maintain at this point has got me down. I was never like this but I guess age is getting to me.

Jeez what a windbag I was on this post. Sorry. But I do feel a bit better. In the meantime we'll just keep driving till it's trade in time. I guess we'll buy a couple of Toyota Corollas. Low maintenance costs and they actually get better fuel economy than the Mini MCS and Coupe JCW by a mile and on regular gas. (But the Mini's are gonna kick my butt on the road. Fair enough trade for me now.)

 

I am new to mini's. I guess this is something for me to watch for. Does the oil catch cans really help this problem? What about Seafoam?

 

So I have an R53 2004 S and it doesn't seem like this is a problem for these models...it looks like just the newer models?

 

Correct: the engines up through 2006 don't have the serious build up problem. It's the 2007+ turbo charged, direct injection N14 engines that are troublesome. The newer N18 (2011+ I think?) may be better.

In any case you are safe.

 

09 mcs, around 40k. at about 30k, check engine light blinked. i ask this to my dealer, and they said that was just a misfire. they just erased diagnostic data and no problems ever since. never did a cleaning for carbon buildup.

and believe me, i am using the worst gasoline in my country. 95 octane without additives, cheapest. and i never drive hard. just plain economy drive under 2k rpm. well, sometimes i ask myself too, why am i using this car? but i am green from genes.

 

Trust me you will be back. The problem will manifest itself again. Get your checkbook ready.

 

Catch can, Seafoam, and methanol injection likely slow down the problem but there's no cure. I use them all and made it to 60k miles with no CEL from this issue but wow what a difference in power when I finally did get a walnut shell cleaning.

 

'07 MCS media blasted (walnut shell) at 75K mi. Quoted me $900 and "discounted" it to $800.

After blasting the hesitation was better, but not completely gone when accelerating.

Was told to add Techron every six weeks or so, which I've been doing and am now at 100K miles and I almost never notice it anymore. I understand that Chevron and Texaco fuels already have Techron mixed in, but I rarely encounter these stations in my area.

I admit that I did not use 93 octane fuel for the first year or so of ownership until I saw the light, and it has been suggested to me that this contributed to the gunkage.

I'm still a bit confused, however, since I was under the impression that with direct injection the fuel never gets to the top of the valves and therefor the quality of the fuel, or Techron for that matter, can't keep things clean.

 

Wow. We're less than half your 'discounted price'. I doubt you would experience a measurable difference in build-up based upon your use of lower octane fuel.