Honda Repair: 1992 Honda Civic idling too high, vacuum leak, cold engine

Question
My husband is overhauling a 1992 Honda Civic, he has had the head re-built and has put it back in the car, now when he starts the car it idles WAY too high, 4000 rpms, do you know how to adjust this or what the problem might be?

Thank you in advance for your advice!

Answer
Mindy,
Sounds like a vacuum leak. Could be as simple as a vac. hose split or an intake gasket leak. I use carb cleaner to locate these, just spray along the gasket and listen for a stumble. Just use caution, carb cleaner will burn!!!!! Best done on a cold engine.
Dan