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BMW X3 - Engining Reving While Braking

I have a 2013 BMW X3 which I just bought a few weeks ago. All seemed fine until on a misty day a few miles from my house I stopped at an intersection. I was applying my foot to the brake, but the engine revved up and lurched me forward into the intersection. Needless to say, I took it back to the dealer where they could not find anything wrong, even after driving it for a number of miles. So I took it back, and all was well for about another week. Then again on a rainy morning, I took it out and just a few miles from home it revved and lurched again when I was stopped, with my foot on the brake. Has anybody had a similar experience, or have any ideas what may be the problem?

Moisture is causing a problem, leave it overnight at the dealer on a rainy night. If they cannot replicate the problem they cannot fix it. There are multitude of options but since warranty covers it no problem mate.

Do you wear the same shoes on rainy days that you wear on sunny days?

I often notice my BMW engine reving at stop lights because my size 11 DD foot, when not squarely on the brake, catches the edge of the throttle pedal. In my case it is no big deal because I drive a stick so my other foot is holding the clutch down.

I recently had some problems with a BMW drive-by-wire throttle and I am not a fan, but trust me, the designers built in a whole array of redundant features that cause this system to go to closed throttle if anything in the system is not perfect…

Yeah, the first thing you need to rule out is your own right foot…

I’ve had this problem on my Corolla, caused by my big clodhopper of a right foot. Rule that out first, before investing any more on this problem.

If not the foot, I’d suspect maybe a problem with the brake booster leaking vacuum.

With the engine warmed up, place the transmission in Park and observe the tachometer. Now step on the brake…Is there any change in engine RPM?? Put your “wet weather” shoes/boots on…Repeat this test… Any difference?