oil leaking out exhaust,and keeps stalling motor only has 3000 miles on it. on 2001 Volkswagen Passat

Put new motor in and it keeps stalling and oil blowing out exhaust took it back to mechic and he said nothing wrong this is the third time it has gone back.

Asked by for the 2001 Volkswagen Passat
take it to another shop and pay for a diag then take diag to him and ask him to repair issue. there is a big problem
sounds like an incorrect installation on all or some of the valve seals. get this fixed asap or you could be looking at a whole new engine. also once the problem is fixed. change spark plugs and get a new mechanic