Hi all. First post to this forum🤔

I am am the very happy (3rd) owner of 2012 Cooper S for the past year. Only 27k miles!!

a few weeks ago I got a check engine message (reduced power) and found that is was “misfire cylinder 1”. Upon advice of auto parts store guy, I changed all 4 plugs. Same error code. So I swapped coil 4 for coil 1 and now cylinder 4 was fault. So I bought a new coil from O’Reilly Auto and the error cleared!

...until today, when I got a flood of fault codes and the engine ran just a rough as last time. P0304, P0302, and P0300 and B2AAA are the codes.

I find it hard to believe that two more coils failed at the same time.

Any suggestions what to try next??

 

While the engine is running, especially during cold startup, go listen to the valvecover near the passenger end. Check to see if it sounds clapity-click, if so you may have a loose timing chain due to failed timing rail guides, the sound is where the metal chain is loose and slaps the valvecover. Your car being low miles doesn't mean those plastic rail guides can sustain all 7 years without cracking. If that's what's wrong, then it'll explain your multiple misfiring because timing could be off.

Another area to look into is the HPFP and injectors. Also there are instances where camshaft/crankshaft sensors are bad to cause misfiring, though less common. Hope this helps.

 

Yupetc, I was hoping is wasn’t that! I cleared the fault codes, swapped #2 and #3 coils, and re started. Now I have 0302 error, but it runs a little smoother. I just ordered two Delphi coils. I’ll post update after they get installed...

 

I installed new coil packs #2 and #3 and no new faults! Runs great! The new coils were Delphi -- same brand as the failed ones, but they look a little different -- hopefully improved!

 

Sounds good! Hope that's it and enjoy your car! It's a blast of fun to drive these cars.