A caller questioned a vinegar smell coming from the dash when the blower fan was running. Tom and Ray suggested that it may be the insulation or wiring for the motor but i feel they missed the big one. The Mini cooper has a cabin air filter that needs to be replaces every so often. I suggest this is the problem, the car was a 2003 and the caller admitted there was no local dealer so this would be something easy overlooked by a shop not familiar with the servicing MINIs.
Yes I would go with the cabin air filter. I had just purchased a 2003 and the filter was in bad shape.I is easy to replace. You will see the cover for the filter under the dash on the RH side.
Or fermenting leaves etc in the area under the air inlet in front of the windscreen.
I had a 03 325i that did the same thing. It was the cabin air filter. Freakin burning wires? What a couple of dopes.