Gave my 245 𖐝k] to my little sister today. She drove it in bumper to bumber traffc for about an hr, w/ A/C on and it overheated (she never looked at the gusge). Now I have had a few cars do this but It seems to me even given the heat (83 w/high humidity) and the traffic and the A/C the car shouldn't have overheated.

I know the problem isn't the thermostadt b/c It was recently replaced.

I'm wondering if it might be the radiator or something w/ the A/C, or both.

Something I've noticed w/ the A/C is that it really doesn't work in traffic or when you stop very often. But it works great on HYW

Interestingly My sister called after the breakdown and I told her to let the car cool and drive w/ out the A/c - which resulted in the car getting very hot but not breaking into the 'red zone'.- Which may help rule out A/C issue

I do not know when the radiator was last replaced, but it was flushed not that long ago. Also when driving around town or on open road the temp stays perfect in mid of guage.

I'd like to diagnos and fix this problem as soon and as economically as possible, any help would be appreciated.

I don't think my sister is going to borrow the car anymore.