just a little background, I bought my 2008 MCS about 37 months ago, and I never had too many issues with the car. I just recently moved from Columbus, OH to Roanoke, VA last month and I've been making a quite a few trips back and forth. Early June, I had the fuel level sensor replaced under warranty and I reported that the car had a strange idle (when I'm stopped somewhere, the needle will not stay steady and will "bounce" a bit). Flow MINI (the closest dealer to Roanoke) didn't find anything unusual. When I drove the car back to Ohio last week, I crossed the 50K mark. I noticed the throttle bogged down once (just a bit) when I tried to pass someone at 4700 rpm, but otherwiseit drove fine. Back in Ohio, the funny idle came up again, so I went ahead and changed the sparks plugs (NGK plugs, same part# as stock). easy operation. Test drove the car, no problems. Later that evening, I was heading out for a late night movie, when the check engine light came on. The car would not rev past 4000 rpm. I pulled over to the side of the road, shut it off, and turned it on again. It started fine, but quickly repeated the same symptoms. I had it towed to Midwestern MINI (a.k.a MAG), and had them check it out the next morning. The tech replaced one over-torqued spark plug but found no exception to other ones I put in. He tried new injectors (the plugs looked a bit fouled) and cleaned up the valves and intake. Cylinders 1, 2, 4 fired, but 3 would not. He checked the wiring harness, no problems there. Finally he find a busted piston ring on cylinder 3 I couldn't believe it, after only 50,000 miles of fairly trouble free performance, my MINI craps out on me!!!! They of course asked me whether I tuned the engine (which I did NOT) and whether I raced the car (which is NEVER). I have never redlined it, and to be perfectly honest with you, I never really shifted over 3500 rpm too often (thats how I kept my MPG around 33-34). I drove it mostly on the highway, and I always had it maintained on schedule. I had the oil changed every 10000 miles, usually by MAG, and I always used premium from Shell gas. I called MINI customer service, and explained my situation, but they replied back with the results of their investigation. Has anybody heard of anything similar happen? And has MINI/BMW NA been helpful at all?
Either way, for a car (any car) to go out this soon just sounds incredibly unusual to me.

 

Several threads on piston issues w/ gen 2's, some tuned, some not, some S, some JCW.

 

What were the results of the investigation?

 

Yes, its seemingly becoming a common issue.

And for those that didn't believe me that it's happening on stock cars....here you go!

 

I just got word from the dealer, that after the repairs were done, the car still isn't running normal.... I'll be driving down there in a few hours.

 

This is getting ugly...please keep us posted. I may be selling this car sooner than originally thought.

 

I'm a bit leery about these 10,000 mile oil changes that MINI recommends. I would think the oil would break down faster in a turbo due to the increased heat and have trouble lubricating the pistons over time. I wonder if anyone had the same problems when they change their oil at 5,000 mile intervals.

 

MINI customer service hasn't called me back yet. I swung by the dealer earlier and they're still trying to diagnose the current problem (cylinder 3 still isn't working after the repair). Looksl like they found a lot of carbon, but thats about it for now

 

While I completely think the 10-15k oil changes are a joke....that is not why the cars are blowing pistons.

I changed my oil every 3-5k with 0w-40 M1. Piston #3 blew at 52k. Oil changes are not the issue lol

It is very interesting to see that most of the failures have been piston #3 or 4. I do know that 99.9% of the time, cylinder #3 and 4 are the worst as far as the carbon build-up goes....

 

I thought I just saw a picture of a failed piston. It seemed to have had something to do with inadequate material beneath the ring groove and with the turbo boosting it's just not enough material.

Anyways, that's what I think I remember seeing.

....Les

 

That supports my theory...

Carbon build-up in combustion chamber is making the cylinder susceptible to detonation AND increasing the heat loading. Add in the diamond head piston with the large gap under the ring lands. Throw in a possible casting flaw in the piston resulting from inadequate quality control procedures. Now rev the engine up to a healthy (but not prohibitive) RPM --> multiple flame front from detonation + boost pressure + weakness from thermal stress = blown piston.

Certainly not a stretch to imagine this as the root cause.

 

0, none, nada.....I change my oil every 3-5000 mi and have been adding Techron plus. I just had my car looked over at dealer.Gave it a clean bill of health.Engine sounds like the day it came off the lot.I am of course a fanatic about changing air filter,oil,coolant,fuel fiter when necessary(by my standards)As I have stated I must be doing something right.

 

The problem with direct injection is that there isn't anything to clean the valves. I've always used top tier gas, techron, and 3-5k oil changes and at 39K on my JCW there is carbon on the valves. I'll have pictures next week. Mine was in at the dealer about 5k ago and they gave me a clean bill of health. But when I looked down the cylinder with a borescope there's quite a bit of carbon build up on the intake valve. HMMM. The way I see it the r56 eng is good for about 50k miles.

Ray

 

Haha the warranty ends there for a reason

 

Since you're only 500 miles out of warranty, are they going to cover it under warranty?

 

In the context of this thread, I can see the carbon build-up in the intake manifold and on the valves hurting performance but not necessarily causing detonation, which originates from carbon deposits in the combustion chamber.

I know lots of folks here on NAM have advised not to bother with fuel additives for carbon deposits (thinking--correctly--that the mixture would never touch the intake components) but I'm starting to think that additives like Techron would be good insurance in helping to minimize the carbon build-up in the combustion chamber to avoid it acting as a detonation catalyst.

My mitigation strategy for the intake is an OCC (if they ever decide to make one for the '11) and go for the walnut shell blaster every 30K miles or so.

 

Not, that I want to jinx my car,but I have over 76 k on my 08 mcs . I. Change my oil every 5 K .

I must go knock on wood. Knock knock

 

Ok, I found the link to the pics. It's here.

....Les

 

I'm hoping so.... I haven't heard from MINI customer service yet...

 

I'm pulling my engine this coming friday. I'll post pics of the aftermath

 

I got word today from BMW NA that will be paying for my repairs... Except for the sparkplugs (go figure). Well, at least $200 is much less painful than $5000 plus!

 

Glad BMW is paying for it. Same thing happened to my not so dearly departed car at 28k. Did 6k oil changes, not driven hard that much and shell 91.

I'd find out what repairs they are doing exactly. On mine they only replaced 3 rings, one piston and all the necessary gaskets, ect. Didn't replace any plugs and the car did not run very well after the repairs. Still in your case, a free repair is better than paying for it.

 

Wow there would seem to be a trend forming at 50k miles, eh? Thankfully I work from home and only drive mine about 7500-10000 miles per year. I am already planning its demise in terms of a trade-in in t-minus 18-24 months, so hopefully it'll be trouble-free after the recent repairs until I can ditch it for anything not made or designed by BMW, lol.

 

I just had the engine rebuilt at 56k miles. $4500 in repairs and still doesn't start and idle normally.

for those interested cylinder 4 blew and cracked the spark plug. Cylinder 1 is having a misfire now periodically