My 2004 5 spd Cooper with 72K started bogg down with what feels like either a missfire or a fuel delivery issue. When I take off from a stand still or am below 3000RPM under load (hill) the car boggs down & seems to miss. This also happens if I punch it at lower RPM.

Does anyone have any thoughts on it?

The plugs are supposed to have another 25K on them and I don't want to replace them if it isn't needed. I really don't want to talk to the Mini dealer about it because they won't tell me anything except "We will have to fix it!" & I would rather not have them work on it. They wouldn't even tell me how to reset the oil life monitor!!

I put 20oz of Techron Fuil System Cleaner in at the reccommendation of the parts guy at the Mini Dealership & that seemed to help a lot.

Should I change the plugs? If so, do I want to use the NGK BKR6EIX plug or the more expensive version from Mini (5 times as much)?

Thanks for the help!!!

Bill

 

Check the distributor terminals for rust. #3 is very likely to be rusty. Clean it up and try again. Next you have to look at the cheapest and plugs are cheap, easy to look at, and if they look crappy, they probably are. Then wires..

If these are original, just change them. They are like $20. and do a lot of work.

 

I would replace the plug wires at that mileage. I would also put a set of new plugs in. While the wires are off check & clean the terminals on the coil-pack like HRM suggested.

 

Thanks, I suspected I would need to do the plugs & wires too. Thanks for the heads up on the coil pack terminals.

It calls for the NGK BKR6EIX plug. Is there something better or should I stick with them? Also, do I need to use a torque wrench for the plugs & if so what should I set it at? I'm used to working OLD cars where it wasn't such an issue!! Do I need to gap the plugs & if so, what is the gap for the 2004 standard Cooper?

 

I use that same plug. If you are running a 15% pulley some folks recommend going 1 heat range colder.

Yes to be safe you should use a torque wrench. I set mine at 20 foot pounds. I also use just a tiny touch of antisieze on the plugs. I also use some dielectric grease on the plug wires & coil-pack.

One caution.... remove the plugs when the engine is stone cold.

The gap should be good, but I always check. From what I remember they are set at .065.

 

Thanks again! You guys are GREAT! No one on any of the other forums I posted on bothered to get back to me at all!!

 

There are some very good threads on here about plugs and wires, read as much as you can. Amazon actually has some decnt deals on the plugs and the wires, as I just picked up a set of Blue NGK wires for the mini for about 25 bucks, and they are a exact fit.
Using the Anti sieze is a big debate on here, I choose not to use it, but read up and make your own choice.
Good luck to you