Thread: Oil in intake hose

Originally Posted by Pinelli

Hi all,
I'm still finding my way around diesels - I've got a small amount of oil coating the inside of the hose form the air intake to the turbo. Is this normal, or is this a sign that perhaps the turbo might need a bit of TLC?
2000 TD5, 180k on the clock, so it's done a few laps of the circuit.

Quite normal Pinelli for any engine that has positive crank-case ventilation routed into the engine intake. (It's an emission compliancy requirement)

If you ever get around to pulling your intercooler off you'll be quite surprised at the amount of oil that coats the inside spaces as well as every hose.

There are a number of 'catch-cans' on the market that when installed, remove the oil out of the intake airstream and recycle it back to the sump thus minimising the oil vapour entering the intake. They also keep you compliant to emission regulations.

End state - it's no real issue or detrimental to the performance of the engine however, if you are concerned, I'd recommend removing the EGR gear, flush out the intercooler and fit a catch-can. (But of course, you will be modifying the emission gear on your car which if found [Unlikely] you can be fined and the car defected and made to replace it all)

This is oil (from oil mist) from the breather hose, that runs from the rocker cover to the inlet hose between the airbox/maf to the turbo inlet. It's normal as long as it's not gobs of oil. This is why the 80k service interval calls for cleaning the intercooler. The oil gradually condenses inside the intercooler (passes through the turbo/inlet).

This is also the reason some people fit an aftermarket device called a Provent. Search will find what you need to know about the Provent.

Cheers!

Thanks guys. Didn't think of the PVC hose.
Yeah, EGR already gone, and the intercooler and hoses cleaned out. No catch can yet. Didn't realise they drained back to the sump, the ones I've seen just get emptied manually every month or so. Is there a place in the sump for the catch can to drain to, or do I tee it into another hose like from the turbo or something?