How hard can replacing spark plugs be? Did it for 40 years.
Replace the plugs with the proper Beru stock plugs on a standard 2009 Mini Cooper(65k). Plug all light tan.

First of all, which is the number 4 cylinder, driver side for the passenger side? Any ideas why I would get rough running at idle and a check engine light after changing plugs. Cylinder 4 miss fire.
Thanks in advance
Mark

 

Driver's side. Did the wire on the coil seat properly?

 

If you mean the high voltage wire, I'm pretty sure. Will check again. I didn't disconnect the connector from the coil before pulling the high voltage lead off the spark plug.

 

Reset the codes, re-seat the coils on the spark plugs and the harness wires on the coils.

Re-test and see if it runs smoothly w/out check engine light.

If light returns, swap coils (#4 is indeed driver side) around and reset the the codes again.
See if the misfire code follows the coil, or stays with the plug.

HTH,
a

 

this happens a lot when the coil isn't properly seated, if you're positive its correct move that coil to cyl 3 and see if the misfire follows. i just had cyl 4 coil pack go bad out of the blue on me.

 

Thanks for all the help.
Was a bad coil. Replaced and all is fine. Man, the car runs so much better. Was changing plugs due to low speed hesitation. All cleared up.
I thought the non-S Mini was a real dog til the plugs were swapped. So much better off the line.

Thanks again