Hi so my ford focus is a bit clunky when idling occasionally stalling. It also hisses, so I googled it and people think it’s a vacuum hose. Car’s have lots of hoses!!! How do I isolate the problem, as I’m not working at the moment so could do without a expensive bill. would it be a fairly easy problem for a mechanic to fix?

Mmmmm ok, to find your vac system you can start from the brake servo/master cylinder (the thing that you put brake fluid in) a big round dinner ish plate size thing behind it (servo) will have a pipe coming from it and going to the vacum pump (diesel) Check that pipe but it’s possible if it’s diesel it will have pipes that feed vac to other circuits I.e turbo electro valve/ egr valve. Good luck but be careful messing under the bonnet if your unsure of what your doing.

I think I’ll wait until my mates back from the F1 as he knows about cars. It’s a 1.8 petrol

small angry snake in air intake or behind dash, best to wear cycling shorts under jeans

To check for vacuum leaks in the intake system you can spray some WD40 around the intake hose and vacuum lines and their joints and listen for a momentary rise in idle revs. Has worked a treat for me in the past to trace down leaks.