Q: I have a 1994 Nissan Altima. It is always fine to drive less than 1 hour, but it is overheated whenever i drive over 1 hour. what part should i check or change? i've changed a new radiator 2 years ago. please give me your suggestion!!
A: Your cooling systems is compromised either by low coolant level, leaking hoses, falty water pump, radiator cap, and finally radiator. I would start buy checking coolant level. Next I would check all radiator hoses. Make sure they are not leaking. Next check radiator cap. Make sure is holding the required pressure. Next check water pump for any signs of a leak. If its leaking it maybe around the gasket area since your able to drive for that long. Finally replace the thermostat. After you have check everything listed above and the problems still exsist, then replace the radiator. Just besure that you check everything list above any signs of a leak.