So I notice that I always get a cloud of light-greyish smoke when I rev the motor (under load - that is, the car is moving) to about 2500 rpm. This generally coincides with the transmission upshifting, but once my revs drop, the smoke vanishes too.

Should I suspect that my turbo is leaking? I can drive around sustained above 2500 rpm and I do not /think/ I see any smoke, but I need to definitively determine this.

Also - I never see smoke if I just rev in neutral.

Ideas?

__________________
1984 300D Turbo, 326000 Km, Thistle Green Metallic