I have a Galaxy Ghia, TDi 1.9, 2000 model. The car has been giving off a lot of whitish smelly smoky vapour which is pluming out of a pipe on the underside of the car. The pipe is midway along on the passenger side just inboard of the exhaust pipes. My questions are: What does the pipe do? What does the white clouds mean? Is it dangerous? Cheers Mark (London)