vacuum hose connectors/elbows - hunting idle

[Mark A]

Greetings, all:)

Just bought a Mondeo Zetec S V6 and it has a hunting idle and lean error codes from the lambda sensors. I've already pulled and cleaned the air filter, MAF, throttle body and idle air control valve (not sure whether to bother with the EGR), but I am also investigating a vacuum leak. I'll give the lambda sensors a clean while the car is "down".

I've taken the entire hose "tree" off that feeds the throttle body and noticed that a couple of the connector elbows are cracked and perished - can these be bought as spares? Doesn't have to be Ford. The ones I need are those coming from the UIM (front and rear), if that makes sense.

Is it also worth checking the PCV hose? That one's supposed to be a pain to get to without pulling the manifold off, but I don't mind just doing the upper as it means I can have a look at the gaskets under there as well. I noticed the UIM is full of oil, and that's a symptom of a blocked PCV, but could it have failed open for a while first and created a pseudo-vacuum leak?

Cheers,

M.