Toyota Repair: 1988 Corolla Waqon Idle, excessive load, intermittent problem

Question
My 1988 Toyota 2wd wagon was running rough and the mechanic replaced the spark plugs which corrected the problem.  However, I notice that when I have the A/C on and stop a few seconds the idle gets rough for a few seconds then normalizes.  This is an intermittent problem and seems to happen when the A/C is on.  Any info is appreciated.  Thanks.

Answer
Check the idle-up solenoid, it sounds like the idle-up system is not working or not adjusted properly, it could also be that the A/C compreesor is putting an excessive load on the engine when engaging, this would indicate a posssible compressor problem.