My wifes 03 mini cooper non s, automatic 127k miles will sometimes act like it wants to cut off while sitting idle at a stoplight or a stand still. It doesnt do it all the time but quiet often. Any ideas of what this could be? You can always tell when its about to do it...It will slightly vibrate, drop RPMS, almost cut off and then the RPMs will jump back up.

Any help is greatly appreciated. Thanks!

 

Start with the basics. Hopefully you had the plugs and wires changed at 100K miles. Make sure the boots are seated properly at both ends of the wires. Check and make sure the coil terminals are not corroded. Use some carb spray cleaner and a rag and/or brass brush to clean them. This was more the case on S models, so I am unsure if it's also common on non-S ones.

On the S models, a reprogram of the computer has caused them to occasionally idle rough. My old '02 MCS did this. Unsure if this was the case for non-S models. There could also be an issue with the fuel pressure regulator, which is a vacuum-operated bulb that is attached to the end of the fuel rail.

 

Adding onto possibles from above post....Are you running the AC a lot when this happens? Sometimes when I run the AC on high I have a bit of a voltage drop and then it comes back. Haven't had any trouble recently but I consulted a mechanic/engineer about it when it last happened and said it was fairly normal. Just adding a possibility to the mix!


Good luck!