Infiniti QX4 overheating

[dollerprod]

Hi about a year ago I stumbled on this site because of a problem I was having my the A/C blower and I found this epic thread and it saved me about $500!

So now i'm back with a different question/ problem. I should also say I am not mechanically inclined, but I can follow directions and willing to learn.. Anyway, the truck has been getting very hot when it is idling on a hot day.

Turning the heat on helps the problem. And moving again also helps to cool it down.

Actually I was taking a four hr drive with my fiance and HER BOSS and husband and we were driving my truck on the interstate. I live in FL and it was about 95 deg that day and very still. I guess the heat from the asphalt was just staying on the road because there was no wind. Point of the story, even driving 75-80 mph didn't help with the A/C on. Had to turn on the heat and that really sucked and was embarrassing. It's hasn't been a huge issue since it's been cooler with winter, but still happens on the warm days.

Anyway, this should be the thermostat? And I should buy a manufacturers part from Infiniti right? and not one just from the parts store? Can I buy it online? Is this what I need to be doing?

It's a 2002 Infiniti QX4.

[PapaSmurf2k3]

Sounds like your fans aren't turning on (could be a fuse or a relay). You should also check your coolant level.

If it were a thermostat, you'd probably see the problem all through winter as well, and it wouldn't matter if you were moving or not.

[dollerprod]

The fan does turn on, at least when the the truck is idling as I turn the truck on and observe it spinning. Coolant is full.

Any idea of anything else I should check? Both hoses are very hot, not just one of them... So the coolant is circulating alright?

Thanks for your advice!

[gwoods]

So sitting idleing do the fans run constant or just when the truck starts to heat up?
2 fans right does turning on the AC make the other fan come on?

How is your oil level? most of the cooling comes oil.
with the truck cool remove the radiator cap post picture of underside of cap and filler neck of the radiator

Any smoke? If so what color, does reving the motor make it smoke more?

[dollerprod]

I will check on whether the fan runs constant or only when hot when I have a chance... I only know of the fan right in front of the radiator but I will look.
Will check oil also...

No smoke.

Here is a picture of the radiator cap




There's a crack on one of the fan blades at the base. Should I replace before falls apart?

[dollerprod]

Bump for any advice. Just thought it might be some notorious thing for the QX4 that was reported a lot.

Anyway, my brother-in-law, who is much more mechanically inclined than me said that he believes it is the fan clutch.

Likely?

[gwoods]

No smoke, coolant and cap look good so probably not a head gasket

Could be thermostat could be the fan. I would replace that fan either way so start there.

[WDRacing]

You're gonna wanna change that fan asap. If that blade breaks it can take out the radiator. This could easily cause a rapid overheat followed by a warped head or blown head gasket.

Hopefully it will fix your problem.

While that work is being done, make sure the water pump is inspected.

[dollerprod]

thanks guys.. Replaced the fan clutch and the temp seems to be doing much better now. Once or twice the temp gauge has gone up to a point I was becoming concerned but all in all it is doing much better and doesn't scare me at a red light. The fan clutch resistance was far too great, so it definitely needed to be replaced. Thanks everyone!

However, I was not able to locate the actual cooling FAN itself. No auto parts store or junkyard seemed to have one. The local dealership did, but they wanted ~$150 for just the fan!
Any idea where I can find a fan?

Again, thanks!

[Jesda]

If Rockauto doesnt have one for cheap, I'd buy a new OEM fan. Check out infinitipartsusa.com


At 11 years, I'd replace the radiator as preventative maintenance. They're cheap and fairly simple to replace.

[PapaSmurf2k3]

You could also do an electric fan conversion or something.

[WDRacing]

You want to change that fan out ASAP. I don't think I'd even drive it that way.