2002 Pathfinder overheating


My '02 Pathfinder SE (4wd, 6-cyl, 115,000 miles) is starting to give me trouble. Last week, I parked and was leaking coolant. It appeared to be from the engine running so hot that the overflow tank was full and spilling. Ran the heat to get it home ok. Went into the local garage the next day. They tested the radiator and found no leaks. Ended up replacing the thermostat. It ran fine over the weekend, but yesterday I used the AC, and the temp gauge started climbing toward the red, so I shut off the AC and ran the heat to bring the temp down. This morning is stayed at a normal temp, because I avoided the AC.

So, I suppose this could be many things. I have yet to check the fan yet myself, to confirm it’s turning on when the AC is on. I would like to think they would have checked this at the garage last week, but I’m not sure. Also, the water pump is original.

I’m going to make an appointment for it to go back in tomorrow. Tonight, I will try checking that the fan is in fact turning on when the AC is on…


The fan for the earlier ganerations pathfinders were just a stand clutch fan that ran off a fan-belt. Did it change to an electric fan in this generation???

Sounds like you may have a blockage of some sort. Try a flush.


When making my appt for tomorrow, the guy suggested that my pathfinder doesn’t have an electronic powered fan. He’s going to check the fan, but he feels like the radiator flow is less than what it needs to be, and therefore when the AC is on, the radiator isn’t effeicient enough to do it’s job properly. So if the fan is working ok, I could be looking at a new radiator. I suppose at 115,000 miles, it’s not unheard of.

Any idea how much a new radiator will run me? I saw some online parts pricing at around $250 for the radiator itself. So I’m guessing it will be in the 400-500 range?


How often do you change the radiator fluid???

Have you ever changed the fluid??

I’ve pulled the radiator on my pathfinders, but only when I was replacing the timing belt. Never had to replace a radiator on one. They are NOT difficult to replace. If it takes a Nissan mechanic over an hour to replace it he’s not much of a mechanic.


I had the dealership do one of the “big mileage” services in the Spring, which included a radiator flush. I know I had a flush also done way back after about 30-40k miles


I have an 02 pathfinder…had same overheating problem. Replaced the thermostat, clutch fan and the thermostat again, still overheated. Flushed the radiatior, everything looked ok, but still overheated. Ended up having to replace the radiator…apparently, when the car was running the hoses inside the radiator where shutting not allowing much water to go through. Fixed the problem, runs fine now. Radiator replacement at Nissan cost $430


Mountainbike here. The problem here is that the overheating could have caused other problems. You could have blown a headgasket, warped a head, or even caused ply seperation in the inside of a hose, restricting coolant flow through the engine.

At this point you need to have the radiator checked for flow and for hot spots (indicating plugged tubes), have the entire system pressure checked, check the coolant for the presence of hydrocarbons (and/or do a compression leakdown check), and check your hoses.

Yes, the original problem could have been caused by a bad fan or a worn water pump (the impellars can erode degrading pump performance), or even a stuck T-stat. Or, you could have had a leak and let the coolant run low. But now you have some additional possibilities.