Another mystery on my hands with our 2011 R55 Clubman. We just purchased this Mini last month, with only 44K miles on it. A couple of days after buying it the check engine light came on. Back to the dealer it went ( not a Mini dealer as there are none in Maine). Supposedly the dealer had it taken to the local BMW 'shop' for troubleshooting and repair. After a couple of days we are told that the BMW shop discovered that the Mini had aftermarket ignition coils installed and that they were the wrong ones for the car. So, supposedly they ordered 4 replacement coils directly from BMW. After a few more days we are told the car is ready so we pick it up and all was well until today. While my wife was driving it today the check engine light came back on. When I got home I put my code scanner on the car and pulled the P0300 through P0304 codes. The engine seems to be running smoothly with no excessive shake or vibration.

Is there something else that could be triggering these misfire codes or did I get sold a line of BS that the coils were replaced ?

 

No, it's very possible the dealer was correct, and the wrong ignition coils were installed. Hopefully, the dealer cleared all the DME codes when they installed the new coils.

The other issues that can cause multiple misfires are:

Improper fuel presssure
fuel contamination
Multiple injector failures (not likely)
Ignition timing
dropped valve seats (not in your case because you said the engine was running well)

If you don't want to take the car back to the dealer due to the distance, you can clear the codes and see if they return. If the faults do return, take it back.

If it was my car, I would take it back to the dealer; their work should have a warranty.

 

This is a complete shot in the dark but could clearing any adaptations (car was used to running with the wrong coils) help?

 

No ... no adaptations for coils.

 

Fuel pressure not high enough, look into troubleshooting the fuel pump or even HPFP if your car has one.

 

Unfortunately, my code scanner is a read only unit so I can't clear the codes. However, it's still under warranty so back to the dealer it goes!

 

Let us know how it goes. Good luck!