Hello,

I have a 2007 MCS whose yellow check engine light came on, when I took it to a dealer(not mini dealer) it had some misfire codes caused by carbon buildup. My warranty expired in June 2011 and the car has 28K miles on it. I read some of the threads on here about this being a common problem with the Mini. Is there anyway the Mini dealer will take care of this? Can you please help me understand how to go about this issue?

Thanks!

 

The only way to know if a dealer will take care of it is to call and ask.

Another thing you can do is run Seafoam through it and then go out and burn the gunk out of it. Your problem may be that you drive like an old lady. You need to put some hard fast miles at high RPM's on it. Remember, the best shift point is at the red line!!!

 

Nothing to contribute to the OP's issue, just wanted to tip my hat to you for this great line

 

Find a station that sells real gas,no ethanol & use it after they or you clean it out. Complain to MINI USA if the dealer wants to charge you for it.

 

haha!

So does that mean that the dealer should take care of this problem even if the car is not under warranty?

I do only use Chevron premium gas on the MCS.

 

Had the same problem with my 07 MCS just recently. Had the dealer do a media blast with Walnut shells. It did the trick. I was also out of warrenty as of May 11. I had 55,000 and I don't think a seafoam treatment would of cured the issue. Gas is not the problem. R56's have direct inject engines. so gas doesn't hit the valves. Do search on Carbon Cleaning, You will find a lot of before and after pics. That is why I decided to do a media blast.

 

I had mine done at the dealer after 50,000 mi on my '08 MCS, and it cost almost $900. No hint that Mini would cover it. It's just a function of the type of engine they used in these models. Sadly, it'll need it again in another 50,000 or less.

 

Blackdog Turbo, It was only $613 for the dealer to do mine. I have started to change my own oil in the fall and spring at the same time I plan to do a seafoam treatment. I also plan on getting an oil catch can and putting it into the system. Hopefully this will help with the carbon build-up.

 

Good line. My wife will sometimes ask, "Are you in a hurry?" To which I reply, "No. I just like to drive fast..."

 

You need to delete the rear PCV hose also, as this is what causes oil vapor to accumulate around the inlet valve.

 

When I had mine done at 34,000 miles I asked what it would cost the next time when I had to pay - was told about $400. It will be interesting to see how much it actually will be $400 - I assumed about 400 means 600.

 

I'm going to chime in on a carbon issue I just had to deal with on my '07 R56 with 70K miles.

About a month ago I started having hesitation issues when I was accelerating hard in the upper gears, or when the engine was cold and accelerating in the lower gears. And I was hearing some engine rattling associated with this. And then the engine light came on.

I brought it to the dealer because I know that the HPFP is under an extended 10-year warranty (due to it being crap) and thought it might be that.

Nope. They concluded I was two quarts low on oil and that was causing a lack of oil pressure, which was affecting the ability of the VANOS system to due its job -- rattling of the upper valve assembly. No damage to the assembly however. So, essentially a $200 oil change. Sucks, because I had just had the oil changed a few weeks prior somewhere else. Either they screwed up the amount of oil they put in, or it was burning oil.

It fixed the rattle, but not the hesitation. The engine light came back a couple weeks later.

This time they concleded it was carbon build up on the valves, preventing them from completely closing and allowing exhaust to escape through the opening.

Because it was into the valves, and not just the plugs, they said Seafoam would not do it. So I had to go with the crushed walnut blast. With labor they wanted to go $900. I got them to knock $100 off and not charge me the extra $125 for the new plugs.


The good news was the valves were not yet scorched. And it runs fine now.

I am going to start putting in Techtron about every four fill-ups to fight the carbon.

Anyone have experience with this product?

Admittedly, for the first couple years I owned the car I did not use 93 Octane, so I may have screwed myself. I've used it religiously since, and actually, I have been averaging 34.1 MPG (a lot of highway driving), so the added cost isn't as bad as it seems. And if it helps prevent an $800 walnut bath, all the better.

 

For Techron. The Corvette world swears by it and I used it periodicly in my C5 convertible. Also, if you use a top tier gas like Shell or BP, it contains a either Techron or a similar additive already in it. It also keeps sulfur off your in-tank gas gauge sensor keeping it clean so the gauge will work properly. The Vettes have a big problem with this issue, not sure it's a problem with the mini's.
I just ran a couple of tank fills of gas with Techron added through my 2007 mcs ( 45,000 miles )and it does seem much more responsive and the engine runs smoother. For a few bucks, every couple go months i'll treat a tankful of gas with Techron and feel I'm doing the right thing for my car!

 

Thanks for the feedback. I typically fill up at Shell or BP. Recently I discovered that Chevron and Texaco sell fuel with Techron in it, but frankly don't see a lot of Chevron and Texaco stations in Maryland.

I was able to buy a "six pack" of 12 oz Techron bottles for $7 each.

 

I don't mean to sound snarky, but it's still shocking that so many people think using fuel additives is going to get rid of carbon buildup on the back of the intake valves on the N14 direct injection engine You either need to use Seafoam in the intake, use a catch can to grab some of the oil vapor before it clings to the intake valves, or manually clean out the ports by hand to alleviate the problem. If you haven't done any of those things, problems are guaranteed to come your way soon.

Yes, this engine is preventative maintenance heavy. Time to get to know your toolbox better.

 

Countryboy, perhaps the reason so many people think this way is because their dealership may be misleading them. I had a long conversation with the techs at my dealer to discuss what I could do to avoid this issue again and avoid the walnut blast.

What they told me is that Techron is the best approach. They also said that Seafoam only gets to the plugs and can't help with the valves.

So I've been going off of what they told me. I don't know you, but you sound like you know what you're talking about. Even if it sounds different than what I heard from the service department.

Oh, and not to sound snarky, but the word is, "preventive."

 

Fuel additives will clean the combustion chamber for sure. I will agree with that. The danger with Seafoam is that you can foul up the spark plugs and you'll also probably log a CEL for engine misfire since the car will run extremely rough after Seafoaming. The dealer will never recommend this procedure because if you dump a can of Seafoam in the PCV pipe way too fast you can potentially hydrolock the engine. I've been Seafoaming at every oil change (5K miles) for 52,000 miles with no problems yet. I'm cleaning my intake tract manually this winter and plan to post what I find so we all can benefit from seeing if Seafoam is working any wonders in the intake ports and on the back of the intake valves.

 

I think a lot of people also do not understand "Direct Injection" and that just adding "treatments" to the gas tank will not clean the intake valves and manifold. Most probably need to read up on what Direct Injection is.

I seafoam just before every second oil change (I change oil every 3K).

And if done properly it should not foul the spark plugs but I have found that I need to change them early, about every 40K miles.

 

I see a lot of you have lower mileage 07s so that could be one problem that you are not driving enough to prevent or possibly lower the possibility of it forming. Catch can is probably the best thing to do but Seafoaming or something similar is a good idea every so often to help make sure that you clean it up.





I like giving my MINI crack cocaine every once and awhile and by that I mean I put 100 octane fuel in it.

 

Thanks all for the good information. Can anyone direct me to more detailed information on how to properly apply the Seafoam treatment for the intake? I'd like to make sure I have a more thorough understanding of how to do it correctly, or more precisely, what to avoid.

 

I'm sorry, but I have a lot of reputable sources who have turned wrenches for 20+ years who all say Seafoam is a load of crap. If anything, I'd say this is most likely caused by blow by, poor fuels, and granny feet. I'd love to see the results of catch can users and those without.

If you clean your intake, I'd like to see the results, but I'm not putting any money on the product.

 

^This.

Here's an illustration of DI:



With direct injection the gasoline is injected directly into the combustion chamber after the valves. With indirect injection, the gasoline is injected over the tops of the valves and let into the chamber when the valves open; thus cleaning the valves. As you can see, with DI, the treated gas would never touch the tops of the valves, therefore it would be impossible for Seafoam, or anything, to clean the carbon build-up on the tops of the valves.

With DI becoming increasingly popular, you would think that businesses would start offering basic carbon cleaning services just as they would any other fluid flushes, etc, and this will become less of a big deal.

 

Thanks, that's helpful. I see that now. So my understanding is that Seafoam proponents believe the product is effective when applied directly to the valve heads, as opposed to dumping one oz. of the product in with each gallon of fuel? How difficult is this sort of application, and what might I screw up if I educated myself some more and tried it?

 

In this case, yes, you have to let it soak on the tops of the valves and then scrub by hand since the Seafoam will never come into contact with the tops of the valves otherwise. With indirect injection, it's arguable that Seafoam would clean the valves as advertised since it is in constant contact with the tops of the valves.

I can't help you as far as cleaning it. I have never done it myself and would be just as intimidated as you are. I've seen a how-to on here somewhere and it doesn't look very difficult, just labor intensive.

 

Got it, thanks.