A challenge fellow focus heads. My 1800 zetec has been idling badly, now 90% sorted thanks to cleaning out the iscv, but theres a hose which has become soft and collapses when the engines running and this seems to effect the idle?? Anone out there had this problem before or know what the hose is called/does.
The hose comes out of the back of the throttle body and then runs under the coil pack into a plastic pipe which seems to go into the engine block?
The question has been asked before as to what this is but no answer posted.
thanks to anyone who can help

 

Hiya mate, it sounds like your breather pipe thats been corroded by oil causing it to collapse, this happens quite regularly and does affect the idle. If you replace the breather, it should run sound.

Debs