Hello all, my new to me 1987 Accord 3dr LXi - 166k miles (We had this type of car 21 years ago, so me and the wife just bought another to restore for her flower business).

Anyway, at cold start engine will rev high (1800 rpms), then drop down to 1200 after 2 mins or so, then go from 1200 to 1800, 1200 to 1800 rpms over and over again. Until I turn on the A/C switch, where the idle goes to 1200 without a lope while in either Park and Drive.

What do you guys think? Vacuum leak, Idle Air Control valve, leaky injector?

Thanks, Brently