overheating already

[Triathlete]

Maybe your ac compressor is seizing up or has bad bearings putting extra strain on the engine?

[ohiovx]

Make sure the electric fan is working in front of the condenser. If your only getting hot sitting still or in traffic, it's not the radiator or cooling system. The fans are only needed when your going under about 30mph. If it goes down when you turn your ac off I bet the electric fan isn't working. The high side pressure in the system is getting WAY up there causing a lot of heat in front of the radiator& the mechanical fan is pulling that really hot air through the radiator. The high pressures also make the compressor work harder.