Our van never overheated, ran great until it didn't. The "it didn't" phase was a CEL.Whats odd though is that I will lose the approximate 1 ounce of coolant in around 2 minutes of pressurizing the cooling system with a Stant 12270 pressure tester used on a cold engine. I would think it would take a significant head gasket leak to push that much coolant into a cylinder in that short of a time period, but maybe it's possible.
After redoing the pressure test 3-4 times refilling the system each time, I wondered if there would be enough coolant in the cylinder to hydrolock the engine. I was able to turn it over by hand without issue and it started up fine afterwards. I get no overheating when driving the vehicle, and coolant temps stay within normal range 203-210F.
Engines can take more liquid through their combustion process than we are likely to give them credit for.
If you're sure it's leaking and you can see the leak, you need to look where you can't readily see.