Buddy of mine won't get on the forum and asks me questions about his rx. Anyway, he rebuilt the carb and now it idles rough around 1100. By rough I mean that every ten seconds or so it blips and stutters. When he switches on the a/c the idle drops to 700 but its nice and steady. ideas?

 

interesting, sounds like a vaccum leak to me
at idle it could be getting a slight vaccum leak disrupting the idle, but when a little bit of load is on it it compensates for that vaccum leak as if you were driving
even the smallest vaccum leak can cause idle hell but not seem as bad while the engine is under load.
check for vaccum leaks the redneck way, a can of carb cleaner and start spraying every part of the engine that has vaccum lines, if you spray and the engines idle changes then you found your leak

good luck
-greg

 

I would check around the AC solenoid on the nest (white dot)

 

thanks, I'll prob go over to his place and do everything for him tomorrow. lazy ******