What needs replaced on a 2002 volkswagen jetta if the car runs hot but doesn't over heat?
The cap to the expansion tank (or a radiator cap) may need to be
replaced. These go bad and allow the temperature to slowly start
rising. Or maybe your existing cap is loose---try tightening it.
Radiator or water pump. Check your maintenance schedule and see if
you are due for a water pump/ timing belt. If the car has over
100,000 miles, the radiator can't hurt. DO NOT USE TAP WATER IN
YOUR COOLING SYSTEM!!!!!!!! pre mixed 50/50 coolant or dilute with
distilled water. Tap water is full of minerals which will buildup
in the fins. Thats' my first guess, I need more info otherwise. Try
changing the thermostat.