Hi,

Been searching these forums for a bit but haven't yet found the answer, so hopefully someone can give me a hand.

I have a 2001 Y Focus, with a 1.6 Zetec-s engine (it's the silvertop one I believe).

Anyway, when I turned the engine off a few days ago I noticed a hissing noise coming from the engine bay. It stops after about 10-15 seconds. It's pretty loud but I can't pinpoint where it's coming from...all I can tell is that it's towards the back left of the bay. Is this normal? If it's not, could it be a vacuum leak?

Also, the idling isn't great. It's not cut out on me yet, but it does shudder now and again. I've cleaned the idle speed control valve but that didn't seem to do much.

Also, most of the info on the net seems to relate the blacktop engine for the mk1 focus. I've heard that eaning the mass air filter could help, but I can't find the maf? I was also told that cleaning the Egr valve helps, apparently the silvertop petrol engine has one??? Anyone point it out to me lol?

Cheers, any help or info will be most appreciated. I'll attach a pick of the engine bay asap.