Our 2005 MCS started cutting out, bucking, backfiring and completely dying about 2 weeks ago. We had it towed to the shop and so far they have replaced the air intake (said it was cracked), changed the fuel filter including draining the fuel and putting all new gas in, changed the fuel pressure regulator, changed the coil and aside from the problem they noticed the harmonic balancer needed to be replaced so they did that. After an invoice for almost $2K and the car being in the shop for 10 days the problem supposedly was cured. I picked up the car and it was doing the same thing within a few blocks of the shop. Obviously feeling like I spent a lot of $$$ for nothing at this point.
The shop has taken the car back in and will start going through everything again but I wouldn't mind some thoughts from the great minds here of what the problem could be.

 

Did they check fuel pressure? How many miles on car?

 

The car has 95K miles on it. They checked the fuel pressure said it was slightly high so they changed the fuel pressure regulator. Car is still in the shop with no resolution.

 

Is the "shop" filled with trained mechanics??
I only ask cause most of the "fixes" seem kinda shade tree...hope this works, hail Mary fixes, than troubleshooting to find an issue....
Some of the items were unfoubtly needed....but none of them seem to scream "i'm the issue"....
Any news on codes?
Did they give you an odb2 with a recorder that captures data so your u can make it do it again?

 

Agree - would think something like you are describing would throw a code. My car cut out intermittently but was low fuel pressure. Your problem almost sounds like a MAP sensor problem but that should cause a code I would think.

 

They have had the car almost 3 weeks now with the exception of me picking it up when they said it was fixed and taking it right back so no ODB2. They have been a good shop in the past and seem to get good reviews however I am also feeling like they are just throwing darts at this point. I haven't heard from them in two days and the last thing they said was it could be the catalytic converter or a problem with something on the supercharger... I am getting frustrated to say the least.

 

Here is the update and the darts have continued to be thrown without a cure so the car was towed to the dealer this afternoon.
In this round they replaced the catalytic converter, fuel pump, motor mounts, MAP sensor and not sure what else along with another bill for $2,000 if I wanted them to release the car. I am frustrated, still have a crappy running car and even worse, I am $4,000 poorer not to mention who knows what the bill will be from Niello Mini when they find the problem and solve it.

 

I'd recommend staying away from this shop in the future. Sounds like they know nothing about Mini's. I would think they have some responsibility to discount your cost if they've charged you $4k and haven't fixed anything.

 

Update:
The Mini has been at the dealer since the 20th and the car has had the issue rear it's ugly head which is a good thing for diagnosis however dealer too is baffled by the problem. They have spent a lot of time trying to diagnose including changing the computer and nothing has provided a fix.
I am changing the name of the car to Mini from Hell I think. :(

 

Any update?

 

Sounds like they have no idea what is wrong and just decided to throw parts at it and hope it goes away. IMO you shouldn't be on the hook for all the unnecessary parts and labor they tossed at the problem.

 

While trying to diagnose the issue, suddenly and without explanation the car started running properly. The dealer told me all they can say is to come pick it up and bring it back when it starts happening again. It started happening again just a few times in the last week so I threw my arms up and gave up. I sold the car for $7K as is and bought a VW Golf. I miss the Mini but I couldn't see putting more money into it or getting stuck on the side of the road again.

 

Sorry about that. Good luck with the Golf.