Hello Everyone,
Not to long ago my check engine light came on so I took it to a local autozone to have my car scanned. Turns out cylinder 4 was misfiring, but I did not notice in its performance. So I purchased new spark plugs and did not put them in right away. Just yesterday I was driving my car and it started to run real rough and the check engine light was flashing at me. It would chug and chug as I got up to speed and then it ran fine until I came to a stop and it idled for a few seconds and then it did the same thing. When I got home I changed the spark plugs and still the same problem. So I'm thinking possibly a bad injector? So I just went to Shell and got STP fuel injector cleaner and fuel hoping this fixes the problem. What else could it be? I have been doing some research and people have been saying things like the coil packs or the high pressure fuel pump. What do you all think? I really need to get this fixed asap! I do have a little time left on my warranty but I was hoping to find the issue myself so I don't have to drive an hour to Mini and then have to pay them $80 for the diagnostic fee, and then another $100 for the deducible. So that is my last resort.

I am driving a 2006 R50
62,XXX miles

My warranty is good to 72,XXX miles.

Any help would be awesome!!!!!

 

My CEL problems revolved around using improper fuel. I thought I was doing OK but found that I was unknowingly buying ethinol and wound up having to replace the O sensor. MINI's don't like that stuff too well. Found out where to get the real stuff and all is well now. Two websites that helped are:
http://www.toptiergas.com/retailers.html
http://pure-gas.org/index.jsp?
Hope it's something simple like that and not a horrible mechanical fuss.
Just a thought, you'll get a lot more ideas from other experiences out there.

 

Gen1 does not have a high preasure fuel pump...it has standard fuel injection (not direct injection like gen2).
fuel injector cleaner can often lower octane in the current tank of fuel...so be careful about possibly making an issue worse if it is due to a mechanical issue.
It sounds like you looked at the basics...might be time to dig deeper...

 

P.S
$80 for a diaonostic fee is dirt cheap compared to throwing almost any parts at the car....so imo, just get it looked at.

 

I have an identical problem that's slowly becoming worse. It started 3 weeks ago. Now, after starting and running for a few minutes the engine mis-fires on the second cylinder. It clears again after a few minutes running and is fine under load. I've only tried swapping plugs and making sure connections are tight so far.

I'm now guessing it's an air leak / engine management issue because if it was something breaking down it would be worse under load ?

 

I would say just check your coils for corrosion. It's a common problem for Gen 1.

 

MINI's don't like that stuff too well. Found out where to get the real stuff and all is well now

 

Also, be sure to clear the code before diagnosing any further. The car may be trying to protect itself, even after the mechanical problem has been sorted.
If you don't already have one, a good OBD scanner is a great tool to have.