How did you make out? I JUST joined this forum as I'm on my way to meet the seller of a 2005 Sapphire Blue SRT6 in Georgia to trade my 02 M3 for and the car I'm buying has this problem.

What occurs most often is that water gets into the area that holds the Vacuum pump and its electronics, drowns the circuit board and knocks out the pump. More than likely if this is the case you will have to replace the pump.

I got the car with 24k for 16995 and am getting decent money for my trade so *fingers crossed* on the off chance everything goes as planned (it never seems to) I should be driving it home tonight, and will get the pump done myself.

Good luck.