1999 Plymouth Grand Voyager Overheating

5 yrs ago my vans temp gauge rapidly started to shoot up into the danger zone. It was a very hot day and I was pulling a steep hill at the time with the ac on. I quickly shut off the AC and switched to full heater and fan. That would bring the temp gauge back down where it should be. All is fine the rest of the year until the summer time. It will happen suddenly and the car has to have the AC on to get this to happen. Is this blown head gaskets? For 5 years no problems with the car and overheating. Like I mentioned, it shoots up fast too! Hard to induce, very hot days with the AC on and under a load like a steep hill.

I have R R radiator, thermostate, verified aux. Fan operation and used the block check but was hard to induce condition. I and going to R&R the head gaskets unless you can think of something else. Don't want to do the heads unless you agree with me. I will donate $100.00 if it saves me the head gasket work but, if if you this as I do that the donation will be $10.00. Untill the next head scratcher.

Hope you can respond fast on this, I'm pulling the trans. To rebuild it. Yeah, I know, why don't I just buy another van. Don't have the money but have the tools and a little know how.

Thank you for having this website availible, if you are able to help me, I will help you in kind.

Paul Schoch