2008 Cooper base is sputtering/misfiring when warm and idling. I took it to the dealership to have it diagnosed and they said it's the ignition coils. I ended up changing those myself because they're easy and they wanted my first born child in payment.

Unfortunately the problem persists. I'm going to change the spark plugs too but haven't yet because I don't have the thin wall socket required to do so.

I've also been told I should change the spark plugs wires (I assumed they meant ignition coil wires), only they don't look easy to change.

My other problem is that I've tried searching "2008 Mini Cooper ignition coil wires" on google, amazon and www.thebmwminipartstore.com only to find that no one has what mine look like. Mine look like this (in green).


What are those officially called? Ignition coil wires? Are they changeable (for the layman)? Should I change them?

Beyond these items I'm not sure what could be causing the rough sputtering/misfiring when the engine is warm and idling. Seems to run just fine when I step on the gas however.

 

There is no reason to change the wires unless there is obvious damage. The wires are before the voltage is stepped up by the coils.

Did you happen read the trouble codes? And if so what where they?

 

I haven't pulled the codes yet. Last time it was listed simply as a "misfire". I did however get the spark plugs changed this weekend, with no result. It's still sputtering once warm and idling. My wife drove it once over the weekend (before the plugs were changed) and said it stalled out on her at a light. I typically drive it in sport mode but she has no idea that exists, which may be why it doesn't stall out on me very often.

I'm going to take it to the dealership to see if they can provide any answers as to what is the cause.

 

go to realoem.com and enter your VIN to find the part number for the wiring harness to the coils. I agree with cerenkov though, the wiring is probably fine. This isn't the old days where there was one coil and high voltage wires to each of the plugs and over time the insulation would break down.

 

As an update, I've finally found out what was causing the problem. And it's not pretty. The cylinder wall was cracked, allowing oil to seep in. The cylinder wall is now scorched, causing the loss of pressure and misfire once warm. The only fix is a brand new engine to the tune of $10k.

 

WOW...how did that happen!!!

where are you located?

 

Hello, I've been going through similar situation - 2010 base with 140K miles and rough idles after warm up and misfires on multiple cylinders, but mainly on cylinder 1. Misfiring only happens when the engine warms up, though. So I troubleshooted with very obvious things - coils, spark plugs, compression test, leak test. But eventually decided to open the cylinder head. While I sent the head to a machine shop, while it's been cleaned up, one of the valve seats on cylinder 4 came off. was told that Mini has this issues often. I think that's what'd happen to the engine and messed up the piston wall. sorry to hear about yours and thought to give you one of the possible causes. for mine, got all 16 valve seats are replaced now and ready to put the head back on this weekend.

jh