I just bought my wife a used 2008 mini cooper s. 6 speed with turbo. Car is bone stock with 54k miles. After about 3 days of driving it. The engine misfired when I tried to go over 1/3 throttle. Had the codes checked amd it was a misfire on all 4 cylinders. At idle it seemed to cut out every once in a while.Took it back to car lot and had them work on it since it had a warranty. That morning the car did not want to start . It took alot of pedal pumping but it started. So we proceeded to drop it off.

when i got there and talked to a mechanic, I told him I thought it was a fueling problem. He pulled the codes and got 4 seperate codes showing a misfire on each individual cylinder. He said he was replacing all 4 coil packs and spark plugs. I again voiced my opinion that its a fueling problem. Since its hard to start after a long sit, cant give over 1/3 throttle withput bad misfire and power was down. Well he didnt listen. They replaced coils, plugs and water pump cause the water pump started leaking on the way there.

It actually ran good without a misfire for 4 days after this fix . Still felt low on power. Then the wife calls to telk me check engine light is back on and its doing the same thing again.

I have read few post about the fuel pump, filter or injectors causing these same issues. So what do u think it is? Car lot is going to just replace the injectors tomorrow. Not check the fuel pressure or filter.

 

The high pressure fuel pump is a known issue with the N14 engine. save them the time and effort, but not the money (it is expensive). If they insisted on replacing the injectors, ask them to look and take pictures of the intake valves so you see the carbon build up accumulation.