So I have a 2002 R53 with 133K on it. This rarely rarely happens but it will stroke like a V8 (or if you want to stretch that "put") It's happened three times for me to notice. When I was in the drivers seat it did that and the revs went down to about 500? Once filming my exhaust and once just about an hour ago warming the oil to check the level. I don't think there is anything wrong just wondering if anyone else gets this?

 

I'm guessing what you are talking about is that the idle will slow down and the motor will start to lope a little....almost sounding like it's got a big chunky cam in it? I think that's a well known issue with the R53's. Mine will do it a few times a month......if I'm sitting at a stop light, I will noticed the idle go down a little bit and it idles rough and kind of lopes/chugs for a few seconds.....if I leave it alone the idle eventually will come back up and it smooths out. Or, I can just rev the motor a little and it goes away.

Lots of people have that issue....but I've never heard a real "fix" for it.