HELP!!! My 2001 Pathfinder 4wd keeps overheating!

Yes, coolant is fine and we have bleeded several times, to no avail.

try bleeding a few more times.

Will do. Thanks. Hey, when I search for parts using my VIN on Nissanpartsdeal.com, it comes back that I have a water control valve. Everything I'm reading says this is a 2nd thermostat. Is this true? If so, could it be the problem?

yes,there are two..one at the water outlet and the other one is at the water control valve is in the coolant pipe at the back of the engine. It looks like a traditional thermostat. It goes in from the top and is held in with a couple of bolts. It appears to be a little over on the drivers side.the one at the water outlet is 170 degree thermostat,and the one at the water control valve is a 203 degree thermostat.the one at the water outlet is the Primary Thermostat.and yes that could be the problem. according to what i'm seeing,"On the 3.5L V6 engines, there is a secondary thermostat (called the water control valve) that can be accessed only after removal of the intake manifold"

Wow! That's what I read. Thank you so much!

First thing I would do is replace the radiator cap and overflow tank cap with new ones from the dealer. Because they are pressure regulated and could be worn or the wrong ones. Second, look down your radiator fill hole (when cooled) and see if the radiator cores are corroded and or plugged. Is your overflow tank still connected to your radiator? and make sure the coolant is properly mixed to the correct ratio ...the water control valve is there to adjust the temperature of cabin heater. for example for left and right sides there are two water control valves to adjust different temperatures. these are definitely part of cooling system. they adjust the amount of hot water passing through them to cabin heaters. by the way if thermostat is new and it is correct one in terms of opening temperature,

Ok. I actually ordered a new radiator and it's coming tomorrow. We will check other things suggested again. I will let you know the results. Thanks again.

you're welcome.post results.

Hi Stevieray1. Well, we have changed both thermostats (170 and 203 degrees), replaced the fan clutch, water pump, ECT sensor and changed the oil, burped and bleed several times and it's still running hot! It's sucking up water, but no leaks. We have now drained all the oil (5qts) and there are a few little bubbles in the oil. This is the only indication that it may have a cracked head. Oh woe is me! The truck sounds good! I think I'll sell the parts on the truck. Anybody interested? I put new tires and shocks and struts on it a few month ago. And, a new A/C compressor and new tie rods! I won't get my money if I trade it in. Thanks for all your help. Don't know what else to do.

Wow! I did buy a new radiator, but never installed it. I still have the Pathfinder, but bought a new car 2 months ago. Good luck!

It was the thermostat. All better now but I didn't know thermostats only last a year. I bought the cheap one this time it will probably last forever.

who told you a thermostat only last 1 year? i changed mine last fall in my ole truck,and the one i took out had been in there since 2006,both are good quality thermostats(Motorcraft)not the Autozone junky ones.. it's a 2000 model f-150 supercab 4.6L with 318,000 miles on the clock. i put around 100 miles a day on it. i am glad you came in and said you found the problem though,because a couple more folks are having the same problem a couple days ago with their Pathfinder..i will pass this on,thanks...

Hey Stevieray1: You won't believe this, but we took the front thermostat out and the Pathfinder is running fine! The heater takes a while to heat though.

Well i be dog gone! ain't that something? glad you got it fixed.also, glad you replied back to maybe help others with the same problem. also,you probably have already checked,but make 100% sure that the coolant level is FULL(check level when cold),then make sure both heater hoses are very hot to hold in your hands,engine running,heater on high..check this after getting the engine to normal operating temperature!

Hi there. Both thermostats were replaced already. Hubby pulled the first one out and it’s been running fine for the last 3 years! I bought this truck brand new in 2001 and it’s still running! Nissan is alright with me. Thanks everyone.