Got a small problem with my turbo, thought I'd ask in here coz there's a lot of people with turbo knowledge in here!

I've got an Vauxhall Astra Coupe Turbo on a 2001 plate. The problem I'm experiencing is that it chuff's blue smoke randomly at low revs/low speeds only when the engine is warm. Can't really notice an blue smoke at 70mph on a motorway so can't say 100% that it doesn't.

I've taken the pipes off tonight, cleaned out all the breather pipes I could find, and I notice there was a fair amount of oil in the charge pipes. There's a breather that goes from the camcover to a charge pipe just before it enters the turbo, when taking this off I notice a track of oil leading from it and down into the turbo. Then taking the pipe off from the intercooler to the inlet also has oil in.

There was some gunge in the pipes that I clean, but I wouldn't expect that it could have caused this?

It seems to use the oil rather rapidly, about a litre every 300-400 odd miles.

Can anyone suggest something that I could try to get to the bottom of this problem??

Just to add the car was recently serviced at Vauxhall, not that I really trust the monkey boys that done it, it was sent back 4 times, and a harsh letter written to the MD because nothing was done right! All I wanted was a stamped service history!

The oil that Vauxhall put in/suggest was shell Helix 10/40 is this what it should be using?

Please HELP!