Wife was driving the 2007 S (N14 engine, ~75K miles) this morning when CEL came on yellow and lost power. When I got home to check it my Scangauge pulled up P0300, P0301, and P0302 as active codes. These are engine misfires multiple and cylinder #1 and #2. I pulled the plugs and cylinder #1? (timing chain side) plug was fouled and smelled of gas. The other plugs were normal brownish/gray. Cleaned the one plug somewhat and replaced. Engine still idled very rough.


So, what are my next steps?
1. Compression test? I have a compression gauge just not sure the best method of testing a MINI and the number in psi to look for.
2. Check injectors? How?
3. Check coil? How?


The car has had the timing chain replaced and high pressure fuel pump replaced under warranty.



I do not have a Bentley manual as I honestly am thinking of selling the car soon and do not want to invest in one. I am a reasonably competent shadetree mechanic but most experience is in classic American V8s.

 

Cleared those codes and ran it some more after swapping coil locations. New pending codes came up:
P0001
P0002
P0003
P0008
P0009
P1497
and several B**** codes that result from the Scangauge not reading codes well. Loud knocking noise from timing chain area too.

 

Carbon?

 

I'm sure it has some carbon build up contributing to the misfires but the sudden onset of lack of power leads me to believe electrical or mechanical failure of some sort.

 

Uh-oh. Can you inspect the chain? At least, look at the plastic guides for wear or breakage?

 

I didn't have time to pull the valve cover. At first didn't hear the noise but now I definitely suspect it's the chain guides again. Talked to service manager and they will cover if so.