Q: I have a 2010 scion tc with about 90k on it and since I've purchased the car its had overheating issues. I took it back to carmax

Hi I bought a 2010 scion tc back last october with 72xxx miles and is at 90k Since purchasing the car its had overheating issues. Took it back to carmax the second day they said they couldnt find nothing then said its a bad thermostat. Car ran great all winter long no issues. When it came time to use my ac again their was no issue. Then slowly started wanting to overheat. I went ahead since the money was right and replaced radiator fans water pump thermostat and valve cover gasket. My friend who works on cars says he thinks its a warped head or head gasket but isn't sure and dont really have the money for inspection. I generally drive with the heat on high if its 80plus outside. Sometimes it wont even get hot until I get to a specific place and for some strange reason itll spike up on the temp gauge. Ive burped the radiator more times than I can count. No leaks neither no exhaust smoke no smells. I had to delete the rest cause I ran out of characters on here

我的汽车有90000英里。
My car has an automatic transmission.