Hey all, I am a new mini cooper owner and have loved my car so fair, until i have have been have problems that are way over my concert level. I have been having a misfire on cylinder 4 in my 2009 clubman 1.8l (or whatever the non turbo is). I have changed all the spark plugs, and then it misfired again, so got a new spark plug coil. Once again misfire. So i got new spark pugs and coil just incase the ones i put in where bad, and still didn't fix it. I was able to stop the check engine light from coming on with sea foam, and then decide to change the injectors and the fuel filter. That was about 2 weeks ago.

So currently It just misfired again, and the check engine light come on, and it is now having trouble starting on a cold start unless i give it some gas and then it works. Any ideas what i could do next. Advanced auto suggested doing a compression test to see if it is a bad head, or something.....

Please help, i am afraid i am going to have to sell the car, as it is costing more then it is worth to keep running good!

 

Do you know what the code numbers were/are?

Not sure if you had a P0302 code or not but the troubleshooting information on this thread is helpful.
https://www.northamericanmotoring.co...2-misfire.html

I've read a couple times that low oil level can cause misfires, but surely that's been checked by now.

 

Could also be a stretched timing chain.

Does the non-turbo N12 engine have intake valve buildup problems? I have a turbocharged N14 engine and it gets bad carbon buildup on the intake valves because one of the PCV dumps into the intake manifold. Over time enough buildup can cause misfires.

 

I don't recall what the actual code is but that it tells me it is cylinder 4 misfire, the computer detects that it is a mini cooper 09

 

Get the code if possible. If the misfire is only with cylinder four, since you already have new plugs and coil, I would pull the plug and look for buildup within the cylinder with a boroscope. Doing a compression or leak down test is a good idea also. I am fairly certain the N12 non-turbo engine has regular fuel injection not direct injection so the intake valve buildup problem won't be as bad as an N14 turbo engine. Try running some fuel system/injector cleaner.

 

This is what the injector looks like, I am going to do the compression test tomorrow, and will post my results. Thanks so much for your help, and letting me pick your brain!