I've been slowly working my way through maintenance jobs on my D1 300tdi, most recently, the exhaust/manifold was blowing, so I took the opportunity to fit a decat downpipe, all fitted fine, with no leaks. However, when checking, I notice I'm getting a small puff of smoke from the back of the turbo body, at least that's where it seems to be. Seems to be only on the overrun after revving the engine.

It could also be the EGR blanking plate, I guess. But is a leak from the turbo body a possibility? What could I check to narrow it down please?

Thanks

the only other place it could leak from would be the pin through the body that connects to the turbo waste gate thingy

bullhorns maybe ?

I would always start with the inlet/exhaust manifold gasket.
Turbo leaks are certainly possible.
The evidence would be black soot marks.

Thanks, I do have an inlet/exhaust manifold gasket, so will try replacing that, and see if that is the issue.

Exhaust manifold gasket changed, some loose studs, but upon reassembly not fix. Glad I did it though as cleaned the intake manifold, and torqued everything up properly. Whilst at it cleaned up the starter motor connections.

So, then removed EGR blanking plate, and sure enough it was blowing. Cleaned every thing up, and reassembled with exhaust paste. Pretty confident that's fixed, but will leave overnight to let it set, and time to clear up and a celebratory beer or 2

Thanks for your help.