Thermostat relaced but still overheating. What's problem?
Radiator replaced in teenage son's car. Radiator still needed flushing. On way home it over heated. Bought and installed new thermostat. Left for home again, it overheated again. Actually, temp gage went to red on gage, then went down, then went up again. I stopped to let it cool. Took off again for home--gage hit red just before arriving in front of home.
Someone said heat sensor needed replacement, another thought it might be gauge sensor switch. Don't know what to do.
I have a gut level feeling teenage son drove car too far after heating. I feel he may have done this several times. I'm concerned it could be a blown head gasket and so does another neighbor. I get neighbors and friends advice because I am not experienced enough and can only take things apart and put'em back together with manuals and coaching. What do I do next after flushing the system out?