I've got a 2008 MCS that has been exhibiting some odd behavior lately. A could days ago I went out to start my car and it acted like there was very little power. The starter solenoid clicked and it tried to crank but then went dead. After this point I was unable to remove my key from the ignition as it was locked in. I have a jumpstart battery so I went back into the house and grabbed it. when I got back out side and opened the drivers door everything sprang to life. I pushed the start button and it fired up just fine WITHOUT even using the jumpstart battery.

I didn't think much of it until yesterday when I jumped in to take some trash around the corner. I got in and it fired right up. I drove maybe 2 minutes and stopped the car while I tossed the trash. When I got back it acted totally dead again. Would not crank or anything. I happened to have a set of cables in the car and asked someone to give me a jump. I hooked up and let it sit with the other car idling fast and it was stronger but still wouldn't crank. I told them to go ahead and go as they were in a rush. I walked back and got the jumpstart battery again and got the same results as with the jumpstart vehicle. a little stronger but not much. I decided to try push starting it since it's a manual transmission. I put the key in and turned on the ignition. The door gong was going off as expected but very quiet. I started pushing the car and as I was pushing the car the gong about doubled in volume. I hopped in real quick, pushed in the clutch and tried to start the car. The starter cranked fine just like it should but the car didn't start. it cranked for about 15 seconds before I stopped it. After that it went back to acting like a dead battery. I had a friend come by and try jumpstarting the car again but had the same response. Finally after a long period of time it started acting strong again and I was able to start it.

that was the last problem I've had. Today I started the car with no problems and took it to an auto parts store. They tested my battery and it was fine. I put my OBD2 reader on the computer and measured the battery voltage as reported by the computer and while running it was 14.3 volts.

Anyone have an idea what might be going on? I'm litterally only a couple thousand miles out of warranty but I bought the extended warranty from Carmax. Hopefully I can get it covered.

 

Even with a healthy reading I'd be a little sceptical about the battery's life expectancy. MINIs do really strange things when their battery is about to die. Do you lock each time you park it for the night? Hiting the lock button on the fob shuts down a lot of stuff that normally remains active which add a small drain.

 

I lock it religiously when I park it. It's the original battery so it's right around 4 years old which is when I would expect it to start dying but two battery tests now show it's fine.

 

The oem battery is good for about 2 to 3 years. Might want to look into replacing it.

 

Double post.