Originally Posted by Jhill

Hmm I'm trying to think if this is normal or not. It's been a little while since I've had an oddball cooling car but I'm thinking this doesn't sound right like the flow in the radiator is restricted but then you say the outlet is same as inlet which is good. Maybe your just picking up the cooler air blowing across the radiator. If only happening with ac on and your temps are all fairly close so flow doesn't sound like the issue I'm leaning towards a possible fan speed issue with ac on. I have not really looked at the cooling fan diagram so maybe I'll do that later but it's not uncommon to have different fan speeds and the ac should put it on most likely put it on a faster setting.