So a few months back my check engine light came on. It was misfiring. Changed the plug wires with new ones purchased from MINI shop (OEM). Fixed the problem and I was all smiles because it was easy.

Now it seems that on a monthly basis or so, I have the same issue. I can feel it happening before the light even comes on. I pull over, pop the hood, press down on each of the plug wires, start the car, and all is good. The engine light then turns itself off after a couple drives.

Of course this is annoying and I know the car is getting older. But what could possibly be causing the plug wire to pop off? I think it's always the same one - far right (I think #4, could be #1). When I push them down it's the only one that feels like it moves.

This is also the same cylinder that caused me to purchase new wires. This leads me to think that it is not the wire causing this. (Who knows, the old wires might have been fine and it had just popped off like is happening now.)


2008 MINI Conv. 124,000 miles

 

How about switching 2 plugs around as a test? How old are the plugs and are they the OEM ones?

 

Changed the plugs same time as wires. Pretty sure I would have gotten NGK.

I suppose I could switch two plugs around. I guess if it never happens again after that then it was the issue!

 

Yes try the plug swap first.

But lets also make sure the plugs are tight, in theory cylinder pressure could be leaking past pushing the wire out.