2002 sunfire surges at idle with a/c on and a/c blows cold at speed, warm at idle Also temp gauge goes up when it is hot out and car is idling with a/c on. No problems at all if I am running the car without the a/c off.

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The temp gauge will go up due to the added load of the AC on the cooling system, and as long as it doesn't overheat you are fine. I would have the system checked for a low charge, the symptom,s fit. You will need gauges and then the pressures tested to find out what the system charge is doing.
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