(SOLVED) 2002 Overheating

See my last post for how I fixed it

So I'm having a problem with my truck and need some advice. It's overheating when stopped at a red light. When I put it in neutral and press on the gas the temp immediately goes down. Also on the freeway the temperature doesn't go up. And it doesn't have a shroud either but I'm seeing conflicting things about it, some saying you don't need the shroud some saying you do. Turning the AC on makes it worse. I'm guessing it's either the fan clutch or thermostat. Any advice is appreciated thanks.

 

First check the coolant and make sure it's full but if the fan shroud is missing that is most likely your problem, without the shroud the fan can't pull enough air through the radiator to keep things cool when the vehicle isn't moving.

 

I did recently replace the upper coolant hose so I'll try bleeding it. Also ordered a fan shroud so hopefully one of these fixes the problem. I'll update with more info here soon.

 

I found a shroud on Facebook marketplace and installed it, and checked the thermostat which all seem to be fine. The only other thing I can think of is when I changed the upper coolant hose I had about a liter of coolant left over. So my guess at this point is air trapped in the cooling system. I tried burping it but not a lot of bubbles would come out. Now I'm stuck and don't know what to do. Any advice? I'm looking online on how to get trapped air out, if there even is any.

 

is the fan clutch stuck free spinning? water pump could be an issue too... many things can cause this.

 

I can move the fan a little bit by hand, about 1-2 blades pass by when I turn it then it stops. When I turn off the engine the fan stops moving right away. Tried to stop the fan while it was running with rolled up newspaper and it wouldn't stop.

 

how clean is your radiator? bugs and dirt impede airflow

 

It's pretty dirty but doesn't look dirty enough to cause overheating. I'll give it a good cleaning tomorrow. I drove it about 20 minutes ago and the coolant level was a little low when I checked it after it cooled down. It took about 2/3 of coolant from that 1 liter bottle I had but it's still overheating.

 

Which way does the jiggle valve go? I'm seeing conflicting answers, some saying at 12 o clock some saying 6 o clock.

 

Alright I've got 3 sources saying the jiggle valve goes in the 12 o clock position for the 2rz-fe engine. Looks like it's 12 o clock for both the 2rz-fe and the 3rz-fe. The 5rz-fe however goes in the 6 o clock position from what I found online. I didn't know this and reinstalled the thermostat in the 6 o clock position. Going to fix the thermostat position , burp it and then take it for a test drive and see how it does.

 

All right the jiggle valve is in correctly at the 12 o clock position. It didn't overheat while driving this time. Got back and let it cool down and was able to fit more coolant in the radiator. This time I'm sure the cooling system is bleeding correctly. Everything's looking good so far so I'm gonna take it for a test drive tomorrow in the heat and see how it does. I'll update this tomorrow.

 

Then the warmer then normal ambient temperatures also play in.

i don`t use the Stock radiator I run a copper /brass one in both my 3.4 engines with no shrouds . The radiators are on the newer side as well.

I could see a problem with the stock setup not using a shroud .

A dirty condenser does a good job reducing air flow when stopped. These 2 issues together perhaps?

I always clean from the engine compartment out no need to push the dirt in deeper.

 

Still overheating but not as bad as yesterday. Only climbing up a little bit from operating temperature. Might be more air trapped in the cooling system so I'm gonna let it cool down and try to bleed more air out.

When I'm at a red light I put it in neutral and press the gas and the temperature goes down instantly. Why is that? The AC clutch wobbles and sometimes the AC blows warm. Could that be causing it to overheat?

 

sounds like water pump issue.

 

Did you make sure to turn your climate lever to full heat? You want to circulate coolant through your heater core to ensure as much air as possible is out of the entire system. I’d also park at a slight upward incline so the radiator is highest. And using a kit to fill helps also.

 

Tacomahound: the jiggle valve for the 3.4 V-6 is installed downward, at 6 o'clock: the image is copied from another user's thread that I saved a long time back.

 

Took your advice and I got it to bleed a little bit more. It still overheats and the needle rises just a little bit past operating temperature. Could a wobbling AC clutch or faulty AC compressor be causing this slight increase in temperature?

 

Thanks for that. I got the 2rz-fe so I had to search around for the correct position for that one

 

What do you mean by it overheats but the needle is just past operating temp (halfway)?

 

The needle is just slightly above the halfway mark of the temperature gauge