I have a 2006 Mini R50 6MT with 146k miles which I have owned since 2005 as the only owner. This summer I noticed that when I'm stopped at a stop light something in my car electrically powered is switching on or off and I feel the car vibrate when this happens. It reminds me of when an AC compressor kicks on and the unit shakes as the extra Amp draw kicks on. But I noticed it is happening when the AC is off too so maybe it is a power steering pump or the water pump. I thought maybe the battery was failing but I hooked in up to my tester and it still at 12.7 Volts. But maybe the battery isn't generating enough Amps or maybe the failing component is starting to pull more amps. Has anyone had this particular issue and can you comment?

Here is what I'm planning to do in order.
1. Replace the Battery.
2. Check Alternator for correct power output.
3. Check and Replace Water Pump. (Probably the radiator and hoses too)
4. Check and Replace Power Steering Pump.

What do you think and thank you for your assistance.

I don't think I would replace the battery if it's showing 12.7 volts. You might check the voltage with the car running as an indication of whether the alternator is charging the battery. The water pump on the R50 is belt driven, rather than electric, so that shouldn't be the problem. Have you tried looking under the hood while the car is running to try to see what's happening?

Are you sure it's not your radiator cooling fan recycling?

Thank you for your comments. Thank you for confirming that the water pump is belt driven which reduces my level of concern. I think it could be the radiator fan recycling because the fan seems to have burned out the lower speed relay again and it is now just running at two settings; off and high speed. It is possible that this problem has existed for longer but I didn't notice it because I could hear the fan spooling up along with the vibration. But this summer I'm running the A/C so I'm not hearing that noise and it sounds new. So I will continue to observe this behavior and if this hypothesis is correct; it should resolve when I replace the radiator, hoses, pump and fan in the next 8 months. I'll post an update after I resolve this issue with the root cause.

Thank you.

I have discovered an unexpected resolution to this problem. I ran Royal Purple Fuel Cleaner with a full tank of gas and the vibration at idle progressively got smaller. After a full tank of gas, there is no more vibration. Incidentally, I was also experiencing an intermittent oil consumption for the past 6 months. I wasn't sure if it was a leak or I was burning oil. But now after cleaning the fuel system; the oil consumption has also disappeared as well.

I have had issues with rough idle before but I have never had any oil consumption from excessive carbon buildup. And it is still possible that something else is going on that I am not aware of.

Has anyone else had this experience before?

I think you should contact your mechanic.

About the oil consumption, your PCV may be the problem there. Depending on what has happened (PCV valve stuck open/shut, plastic PCV line-in busted) could determine the amount of oil that your MINI is consuming. Also, check under the block on the backside for any visible leaks that would indicate one of the other obvious sources, my first guess would be to check the oil filter housing gasket area. This leak consumes massive amounts of oil with each drive and makes an indeterminable mess as it drips onto the spinning axle while cruising and covers the right control arm with oil. My second guess would be the oil pan gasket, which tends to blow out when the PCV valve gets stuck in the closed position, an easy leak to find as it will be staring right back at you as soon as you slide under there. My third guess would be the valve cover gasket, which also tends to leak out along the backside of the block (again possibly resulting from an old PCV valve), just reaching back there from the top can verify this leak. Lastly, is there a noticeable collection of oil stains in your driveway in the ballpark of the front, left-side? If so, you may need to have the golden crankcase sensor o-ring replaced, this pricey little leak can rapidly get out of control if not attended to, unfortunately it is also the most expensive oil leak to repair (unless you are capable of putting the MINI into front-end service mode all by yourself of course.) Hope this helps, let us know how it goes.

Thank you Wisky B for your thorough post. The Fuel Cleaner dealt with most of the vibration but I would still have a small one from time to time. This week I swapped my spark plugs out and oh boy; where they dirty. Two of the electrodes were worn down so the gap had increased. New NGK plugs and back to silky smooth. I changed the plugs around 30k miles and 5 years ago with NGK Iridiums. I'm shocked they look so bad. So I'll be swapping them out more often. Thank you to everyone in this forum. Final Outcome: No more vibrations and no more oil consumption.