Can anyone tell me which hose this is that's leaking a little oil? It connects to the side of the main air duct. Does it need a new O-ring, or do I need to replace the entire hose?

 

Just a guess but PCV?

 

GOOD GUESS!

It is actually the CCV (Crank Case Ventilation - Big Time name) aka (PCV) fresh air induction tubing. The oil mist is showing that you have back pressure in the system.

 

OK, so what does that mean in terms of needing to be fixed? I've seen it suggested that the CCV valve is an integral part of the plastic valve cover, so I need to replace the entire cover rather than a simple $10 valve.

 

As long as there is not excessive blow-back as to where it will foul the throttle body (and that does happen and the reason for throttle body service).

Check your OWNERS MANUAL for suggested service. An oil separator may help if excessive. In the older days, fresh air was sourced from the air cleaner/box so the oil mist contamination would have less effect on fresh air ingestion.

 

I have the FSM, and it's not all that helpful. It states that the 2.0L Zetec uses PCV, not CCV, but it doesn't say anything about the PCV valve being in the valve cover - it suggests that it's actually somewhere near the bottom of the engine. I need to crawl under and take a proper look.

 

What is the application?