im having some overheating problems..after about 20 mins of driving my car it starters to overheat..but for some reason it jumps from all the way hot and goes back to mid mark at idle..whats up with that..no white smoke while i drive..no sweet smell like im burning coolant..i figure out my fans werent cuttin on so i jumps the plug so they stay on..but im still getting the same problem...could it be bad radiator or water pump..if so i can i tell..please help thaanks

 

if it jumps from hot to middle, it prolly means there is air in the system, unless there is a leak somewhere. Bleed it first

 

how do i go about doing that