Argument with myself.

Jennifer, don't feel bad- the 21st Century cars are complicated mechanically- anybody that owns one will need a GOOD mechanic- by good, I mean someone who doesn't just guess but diagnoses what is wrong- and repairs it economically- don't overheat that engine

My apologies by don't have a radiator cap, my intention was to day, I don't see one anywhere (which I thought was insane!) that I can access, only the coolant overflow reservoir and cap. I didn't necessarily check anything yet, because i wasnt sure where ti start exactly. I added coolant to the system and let run with no pressure in the until coolant ran through the system and air bubbles were expelled then replaced cap. Now my old school brain thought if the coolant ran through the system when I burped it, the thermostat must have opened up right? And thank goodness in the super short distances it did get hot, but never "redlined" and maxed the temperature gauge out, and I was able to shut it down and cool entirely before proceeding. I guess I'm just perplexed at it overheating on driving even a couple blcks, but could idle for the couple hr process of burping the system several times and never even get elevated?

Thanks for your answers guys, I was raised on the mentality of confirm all the simplistic options first, and the fact that this belt started squealing at the same time, I decided to run that down before I panicked about expensive repairs and tearing down the engine. What I found was the water pump pulley was moving, but only barely, because the belt is sloppy and loose around it, it's not busted of course, but looks worn and tired. Not sure if it would cause my problems, or if it will fix it, but it's the easiest, cheapest next option I have that I can think of. Wish me luck and let you know how it turns out.

Oh btw, fan and fan systems functioning properly, it all looks good at idle, and I can hear it kick on in drive well before temperature gets dangerously high, it's just not enough to cool it alone with whatever else is going on.

Tada, tensioner pulley was completely deteriorated, thanks for letting sound board with you guys. Used to do that with the old man, and was lost without being able to make that call, so thank you sincerely and yall take care.