let me give you some friendly advice, as I just completed doing a TON of research.
I was on considering a 2012 Mini Cooper S and a 2012 VW GTI. Wound up going with the GTI.
Make sure you do your research on Mini Cooper, particularly the S version. Lots of good info is available on northamericanmotoring forum.
I think carbon build up is a real issue, as the poster above notes BMW changed the design slightly to attempt to address this issue, but we don't know whether it actually corrects or not. Lots of people put "oil catch cans" on these cars as a band aid fix.
Luckily the carbon build up can be fixed, even if your car suffers from it....BMW/Peugeot seem to have particular trouble with carbon build up in this direct injection engine, whereas others (like Cadillac with its DI engines) do not.
But I think carbon build up is should be the least of your worries. This is just my opinion based upon a lot of research, but I personally feel the Prince engine (PSA/Peugeot) is fatally flawed and likely to suffer from timing chain problems.
The number of engines requiring timing chain issues is staggering, the guides are plastic, there have been many, many revisions of parts (i.e. at least 5-7?) and the incidents still seem to occur. There is a piston that is engaged by oil pressure, and when these cars are started cold (as is the case every day), if everything is not exactly so, the piston won't fully engage, the timing chain can rattle against the plastic guides and/or stretch over time because its not getting properly lubrication...)
It seems very normal, almost a given, that you wil have a timing chain issue within 50k miles or so, which to me is absurd and not acceptable.
I'm used to BMWs and their problems/quirks, I have no problem with window regulators, etc etc but the Mini Cooper, particularly the S variant (which is the only one worth getting), has the potential to suffer from a number of significant problems:
1) premature clutch wear;
2) timing chain (aka death rattle);
3) carbon build up;
4) failing thermostat (not a huge deal, easily replaced but will cause failure to start and problem is so prevalent even in 2012s there is a wait for parts).
Don't take my word for it, research this for your self, and you will see the number of owners who have timing chain and other power train issues with 50K or less miles is staggering.
My good friend, Chris Connolly who lives in Berkley, Michigan, just had his timing chain replaced on his 2011 Mini Cooper S with 29,000 gentle miles (it's his second weekend/fun car) at Motor City Mini.
Granted it was under warranty, but jesus christ, what a joke. And this guy is in his mid 40s and doesn't drive like a hooligan, and is on his second (and last Mini).
Car was in the shop for a week, and the problem is BMW still jacks people around on the warranty, they keep trying intermediate repairs before doing a whole replacement.
It was just weird to me to read about so many people having this problem, and then sure enough my buddy Chris has it on his Mini.
I love the car to pieces, but just couldn't bring myself to buy a car with a long history of serious, known powertrain issues.
Finally take a look at Consumer Reports for what its worth, the S version is ranked as WORST RELIABILITY, one of the TOP FIVE WORST USED CARS TO AVOID, etc etc.
If you are ok with checking the oil literally once a week and being prepared for expensive engine repairs, go with it (despite all of these issues, I almost still bought one, but then my common sense kicked in and said why are you considering this, there are too many other good choices out there).
Lastly, take a look at the cost for an extended warranty on a Mini....$3500 or so...BMW clearly knows how much it costs to keep these cars running out of warranty...
Have had the GTI for 2 weeks now and love it...
Go in with your eyes wide open (and your wallet) if you plan to buy and drive long term, or maybe consider a CPO and dump it before warranty is up.
It is my impression these cars make BMWs look like Toyotas from the reliability point of view....and I am not bashing MINI, love the design, but just can't tolerate significant powertrain issues...NFW, not in this day and age.
This all comes from a 37 year old guy who has driven lots of cars, and is well aware of the joy (and heartbreak and problems) German cars can bring, like BMW and VW, so I am used to putting up with a fair amount of BS in the German maintenance/repair game...
Last edited by tagheuer; 04-09-2012 at 08:36 AM.