I have a 2007 Mini Cooper S with significant Cold Start Issues after sitting. Took to dealership thinking fuel pump. Was instructed that I have significant carbon build up on the intake values and that was the cause of the problem. They then asked for $450 to clean the carbon out, which I did not have at the time. I have attempted Seafoam in the Gas Tank and I have also completed a couple of treatments directly in the Vacuum tube which have generated little to no smoke and have been unsuccessful. I bought the car used with 62K miles on it and I do not know how it was taken care of prior to me having it. It is in great shape otherwise and have not had any other problems. Please let me know your thoughts as I am not sure if it is past the help of Seafoam, or if I could clean the valves myself, or if I to buck up and get it cleaned out.

Thank you to every and anybody that contributes.

Great to be a part of this site.

CB

 

Mechanically removing the carbon is the only way. From what I've read here, the dealers are walnut shell blasting the ports to remove carbon build up. Someone on this forum has cleaned them by removing the intake manifold and scraped and wire brushed the intake valves.

Unfortunately it is something that happens with many direct injection engines, the fuel is injected directly into the cylinder, so it doesn't have the opportunity to wash off the oil, from the Positive Crankcase Ventilation system, off of the intake valves as it does with port injected engines.

Get it done and then put an oil catch can in the PCV line to collect the oil before it get onto the intake valves and bakes on.

Just search "Oil catch can" on these forums and you'll get more than enough information about them.

Dave

 

Thank you so much for taking the time to reply to my thread. I was pondering removing the Intake Manifold and cleaning with a wire brush, but I do not have any experience with cars and engines. If it is something easy that I can figure out how to do in a weekend then I would love to try it, but I don't know. Do you think it is worth trying or just suck it up and take it in?

 

If you have the dealer manually remove it, it will bring your valves back to a mirror shine new. Then from there, just do what Dave suggested above with the OCC, then just put some seafoam in the PCV line every 10K miles or so, you should be aok from there on.

I am bit surprised at this point that MINI USA has not stepped up to this issue. Carbon buildup is a recognized issue due to the design of the engine, and the very fact they have now equipped their dealerships with these walnut blasters demonstrates their knowledge to a pre-existing problem.......

Maybe if you can, speak with the service manager and propose that they either make a good will repair or make some concessions on the price quote for labor.....

 

i am experiencing this exact issue right now. luckily, i'm still under warranty for another 800 miles. I asked the dealer to see how much it'll cost when it's outside of warranty and it would cost $600.

 

the dealer where i live will do the carbon buildup cleaning under warranty. however, out of warranty...

 

Thank you. I agree that this is an issue that even should be covered on an extended warranty from Mini as the problem usually begins post 60K miles anyway. Will I be able to handle the OCC install by myself? I will see what I can do about negotiation with the Dealer. Would you recommend just Mini Dealership or a shop that works with Mini's?

 

I would hedge towards the dealer. They have the walnut blaster to manually remove the deposits. Other shops will just do the best they can not removing 100% of the deposits leaving areas for the cabon buildup to accumulate all over again......Additionally they don't carry OEM gaskets. I personally would never use aftermarket gaskets in a DD as they are total crapola......

 

Thank you! I visited the Dealership and spoke to them about it, and they told me to contact Mini as they stated this is a known problem that is occurring post 50K warranty, and that Mini is aware of the issue. Well I contacted them and they were awful from a customer service standpoint and they just kept reiterating information about the warranty. The Service rep feels as though Mini should cover at least part of the repair, but I will be going back to the dealership to see what can be done.

Another quick note, 2 times in the past 2 months I got the yellow engine light with it half filled in with yellow and the car had decreased performance, then the next time I started it the car was fine. Not sure what this was or if is was related to the Carbon Build up. Any ideas????

 

DI is great but it does have its issues. Im hoping running a can of BG 44k every couple of fill ups will help alleviate this issue.

Also if the dealer is using the walnut blasting method how do they remove them or are they removing the head?

 

Nothing that you put in the gas will help. The fuel is sprayed directly into the cylinder and so bypasses the intake valves, so it can't wash the oil deposits off of the valves, like on cars with port fuel injection.

As I understand it, the head isn't removed to clean the valves with a walnut shell blaster. The intake manifold is removed and the engine is rotated so that the valve to be cleaned is closed, then the back of the valve and the intake port is blasted with air and ground walnut shells. The walnut shells are harder than the carbon deposit, but softer than the steel valves and aluminum head, so the result is sparkely clean valves and intake ports.The ground walnut shells and carbon are removed at the same time as the valves are blasted, with a vacuum attachment on the shell blaster.

I don't think it would be difficult to make a ground walnut shell blaster for use at home, you would have to have an air compressor and a shop vac, as well as a hopper type sandblaster that you would fill with ground walnut shells.

Dave

 

Another quick note, 2 times in the past 2 months I got the yellow engine light with it half filled in with yellow and the car had decreased performance, then the next time I started it the car was fine. Not sure what this was or if is was related to the Carbon Build up. Any ideas????

 

After reading other posts and yours, it does not seem that it would be too difficult to buy what you need and do it yourself rather than give the dealer $450-$600 to do the same thing. You can get a half-decent blaster at Harbor Fright for roughly $100 (less if you get it with a coupon or a 20% off coupon) and the walnut media for about $20:
http://bit.ly/hfblaster
http://bit.ly/hfwalnuts
You would still need some way to contain the walnuts from getting all over and into everything in the engine compartment - a shop vac held by another person might do the trick - I wonder what the Mini dealers use?

Of course, I am assuming that you already have an air compressor and a place to work in it at - otherwise the dealer would be your only choice.

I am not saying this would be real easy to do (nothing ever is), but if mine ever has buildup issues and it is not covered buy Mini, I will try to do it myself before I pay them a zillion dollars to clean it. I think it would help others if we can think of alternatives rather than be at the mercy of the dealer. If anyone ever does it on their own, it would be nice if they could post info and pics of their setup and procedure.

 

Why bother ? Most R56's with these issues are still under warranty, and if you push for it - possibly a "Good Will" repair.

 

Grey Raven

Unfortunately my car is just out of warranty, so I asked for a good will repair from dealer. They suggested that this is a known problem with Mini's which is why they created the cleaning technique, and that I should contact Mini USA and see if they can help in the repair. Well, I have called twice and spoke to two different supervisors and no dice. They are not willing to even help with the repair, and I can be quite persuasive. I am disappointed that after explaining that I purchased this car used with 60K and I was not able to take care of it prior to that and 2 months after purchasing I am met with this issue and nobody wants to take ownership.Just wanted to update you. I plan on going back to dealership and see what they say now. I will keep you all updated.

CB

 

Did they tell you how they made the diagnosis? Obviously, the carbon can be seen if the intake manifold is moved aside, but I doubt they did that.

Another question: Is this an auto transmission? The reason I ask: https://www.northamericanmotoring.co...n-buildup.html

I certainly hope you can get this resolved without a large outlay of cash.

 

They did not tell me but I read the report and it indicated that they removed the manifold to discover the problem. It is a manual.

me too

 

I'm not sure that taking care of it under the 62k miles would have solved your problem. My 2009 MCS with 31k miles is in for a second carbon cleanup (the first was at around 20k miles when they also replaced the HPFP). I've used nothing but high quality premium gas in the car since the day I brought it home.

Seriously considering a trade in when the warranty is up, as much as I love the car. The aggravation and the time it's been in the shop in less than two years lessens the joy :(

 

I hear ya. I took it in last week and they cleaned it up and replaced the HPFP. It is run fantastic right now and hopefully that continues. I have heard by installing an oil catch can helps to relieve this issue.

 

How hard to people drive their cars? The service writer at my dealer said they see the buildup issues with cars at higher mileage when they drive the cars really hard (like me) supposedly it blasts the crap out....

I mean people who get it at 20/30k miles are you gentle/sane drivers? or are you full throttle everywhere?

 

With the design of these engines the harder you drive the car the more oil mist is generated.

On a old style port injected or carbureted engine you could drive the car harde to clean the valves. That doesn't work with a direct injected engine.

 

I am a drive it like you stole it kind of guy and my car is in for its first carbon cleaning at 26k miles. I will have to ask if this carbon cleaning is covered under my extended maintenance plan.

My car has also gone through a set of tires, front and rear brakes, and two belt tensioners. I doubt that I will be keeping it past its warranty.

 

Considering you are a "drive it like you stole it kind of guy", how does a set of tires and a set of brakes with your driving habits become some sort of an excessive maintenance issue with your MINI?

 

my 18,000 mile mini has has already gone through the carbon cleaning process, two HPFPs, and just to make it interesting, a battery. All replaced under warranty, but this is not a good sign for a long term relationship

 

I expected the brakes and tires. It is the tensioner failing twice in 6 months, the carbon build up, and many other things that give me pause. I don't want to spend a fortune maintaining/fixing it after the warranty is up.