If I rev it up or drive it around it won't overheat. I checked both radiator hoses and they're both cold enough to hold and fans do come on.
Jun 19, 2022 at 11:23 AM
Overheats only when idling
2004 TOYOTA SIENNA
RUBEN541X13
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Have you checked the coolant level? Here is a guide to help:
https://www.2carpros.com/articles/how-to-check-engine-and-battery-pack-antifreeze-levels
If okay, it sounds like the thermostat is stuck closed or the cooling fan is not working. This guide should help us see what's going on. Then we can fix it.
https://www.2carpros.com/articles/engine-overheating-or-running-hot
I would check the fuses for the cooling fans, here is a guide to help and the fuse locations in the diagrams below:
https://www.2carpros.com/articles/how-to-check-a-car-fuse
I have also included the wiring diagrams for the cooling fans so you can see how the system works and which fuses to test. Check out the diagrams (below). Let us know what happens and please upload pictures or videos of the problem.
https://www.2carpros.com/articles/how-to-check-engine-and-battery-pack-antifreeze-levels
If okay, it sounds like the thermostat is stuck closed or the cooling fan is not working. This guide should help us see what's going on. Then we can fix it.
https://www.2carpros.com/articles/engine-overheating-or-running-hot
I would check the fuses for the cooling fans, here is a guide to help and the fuse locations in the diagrams below:
https://www.2carpros.com/articles/how-to-check-a-car-fuse
I have also included the wiring diagrams for the cooling fans so you can see how the system works and which fuses to test. Check out the diagrams (below). Let us know what happens and please upload pictures or videos of the problem.
Images (Click to enlarge)
Jun 20, 2022 at 12:04 PM
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The cooling fans work. I replaced the thermostat, and it still overheats on idle only.
Jun 20, 2022 at 2:54 PM
Does the engine boil over at idle? I have seen where the water pump impeller becomes loose or is broken which doesn't allow the coolant to flow when idling. To be sure the water pump needs to be removed here are the instructions to do so in the diagrams below. Check out the diagrams (below). Please let us know what happens.
Images (Click to enlarge)
Jun 21, 2022 at 9:10 AM