Air Conditioner causes rough Idle

I have owned for 10 years it has 140000 miles on it. Tune up was done at 110000 (2nd). I want to say it started 2 to 3 mos after Tune up. I normally do not use my A/C but its been hot lately.

And its idling as you described.... It had a problem at 110000 where it would almost stall in reverse. The Tune up fixed this, the mechanic said it could of been due to Bosch parts installed the first time. He installed dealer parts.( Cap, Rotor, Wires, Plugs ) Fuel Pump was also replaced at this time. Fuel Pump has been replaced twice. The following items have been replaced Fuel Pump ,Alternator, Serpenitine Belt, Engine Gaskets Intake, Valve Cover. Vacuum Line the one that runs under the air cleaner. Air conditoners and windshield wiper motor. Driver side window motor.

Thank You
Rick38

Dealer recommends every 80000 with the platinum plugs. This problem started a couple months after the last tune up.I also Inspect the cap,rotor and wires every year. The car idles and drives fine. Only when the A/C is on do I I get the rough idle.They had it hooked up to the machine last month looking for the vacuum leak. I do not think the dealer would of past up the chance to sell me a tune up if that was needed. I was hoping it had something to do with the vacuum leak they found and fixed. But it did it on the way home. Their suggestion was to bring it back, but before I do that I would like to have some kind of idea what it might be so they dont lead me the wrong way.