Hi,
I am hoping someone might have had a similiar experience or some idea what the loud pop I experienced tonight could be. I have a 2004 Cooper S with 64,000 miles. Tonight while driving home I was stopped in traffic and there was a very loud "POP". Sounded like someone threw a rock at me or shot the car with a gun. The sound came from the passenger side of the car. I had the windows rolled up and the stereo was loud, but the noise was so loud inside the car it really scared me. The car continued to drive fine, no lights came on. When I was able to get to a parking lot, did a visual inspection, which was difficult since it was dark and rainy, but everything looked ok. I just checked the car in the garage and it is not leaking any fluid.
Any idea what this could have been??? I'm a little worried to drive the car if it could be a serious engine issue. Thanks for any insight anyone can offer!

 

probably kicked up a piece of asphalt or something... if you have a garage peek around with a flashlight and look for scrapes on the underbody.

 

I also had this happen a while ago, Recently realized what it was. The Factory rear sunroof screen had dislodged slammed open. Sounded almost like firing a gun in the car.

Unlikely its the same thing, but another thing to check.

 

I've backfired through the intake and blown a clip on the MAF pipe, but the car will run like crap until the seal is fixed, so you'd know if it was that.