My truck keeps overheating, ive changed the thermostat,waterpump,clutch fan, and it still over heats but only when its warm outside. Ran my scantool cuz my check engine lite was on, codes-311(thermatic Air sys inoperative during self test), 332(EGR flow insufficient). Not sure wut these codes mean and could eather be causing my overheating problem??

 

Are all the thermactor air pump parts on the truck?
The EGR valve could be working , but the position sensor may have a problem
Has the EGR system been disabled?
What does the radiator look like inside at the cooling tubes, heavy corrosion?
Has anyone messed with the ign timing?