Engine running hot
Thread Starter
10th Gear
Joined: Nov 2016
Posts: 12
Likes: 0
From: Wa
Engine running hot
Hi all, re: 2006 Rx330, 131k. A few days ago my temp needle moved up and radiator fan kicked in. Even with the fan running, engine stays warmer than usual. See no leaks. Thermostat 2.5 yrs old. Suggestions? Thank you
Pit Crew
Joined: Feb 2017
Posts: 209
Likes: 67
From: New York
Wait till the engine is cool and remove the radiator cap. If the level is low you probably have a leak somewhere. Any signs of a coolant leak where you park it? Try to look around the water pump and engine compartment for signs of dried coolant staining. While rare the 2.5 year old thermostat could be a problem.
And of course check the level of the engine oil.
And of course check the level of the engine oil.
Thread Starter
10th Gear
Joined: Nov 2016
Posts: 12
Likes: 0
From: Wa
Thx for the reply. No leakage anywhere. Antifreeze level ok. I have a strong feeling thermostat is not opening fully. When temp needle moves up, radiator fan kicks in and it cools off some, but fan stays on for long periods and engine still warmer than normal, first time in 7 yrs this is happening. Now, is it a good idea to replace the water pump and/or anything else besides the thermostat while in there?
Thread Starter
10th Gear
Joined: Nov 2016
Posts: 12
Likes: 0
From: Wa
When thermostat was changed, ~~2.5 yrs ago. Needle does not get to the HOT (red area) but it is staying between 2nd and 3rd line, from the bottom up in the temp gauge. Fan stays on just about the whole time I drive it, especially city driving. Has not done this in 7 yrs. Should I be concerned?
Lexus Fanatic
Joined: Sep 2010
Posts: 26,190
Likes: 4,380
From: Alberta
Do you have a code reader? Would be very helpful it will tell you actual engine temperature not what the gauge says which is "fuzzy logic" not the most accurate. Fans should not run all the time.
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Thread Starter
10th Gear
Joined: Nov 2016
Posts: 12
Likes: 0
From: Wa
Water Pump was not replaced, just the thermostat. And not sure what coolant the mechanic used. Well, if wp can start going bad without leakage evidence, then that’s prolly the issue. Only 131k but, still, 17 yrs old. Do you suggest replacing drive belts and timing belt as well? Thanks
Pit Crew
Joined: Jan 2020
Posts: 101
Likes: 12
From: QQ
I would borrow or buy a pressure tool and check for leaks in the coolant system before you go and replace parts. There's a write-up here for replacing the pumps. If you're going to do the pump, replace the belt. Its very cheap.
Thread Starter
10th Gear
Joined: Nov 2016
Posts: 12
Likes: 0
From: Wa
Is it possible for antifreeze being the issue? Old, needs changing? Twice in the past month I added about a quart of water to the reserve coolant tag. Could that have “weakened” the antifreeze? Also, when antifreeze was put in after thermostat was installed, no telling what they put in. A good idea to empty and refill? Which name brand is recommended for this vehicle? Thanks
Pit Crew
Joined: Jan 2020
Posts: 101
Likes: 12
From: QQ
Its not your antifreeze. For this vehicle, the antifreeze color is bright pink or red if aftermarket. Toyota SLLC, Zerex Asian, or SuperTech Asian. Coolant never leaves the vehicle. If it is low, you have a leak. If you pressure test the system, you can verify it.
Driver
Joined: Apr 2014
Posts: 88
Likes: 4
From: Onatrio
I would inspect the radiator…the thermostat is typically the most common issue and if you’ve replaced it and feel confident in it, then I would check the rad. Visually inspect the fins of the rad. If you have a mesh bug collector in front, I would remove/replace it. If the car is older and been thru several rad shops or mechanics I would take it to reputable service centre for a rad flush. Just some food for thought.🤙🏻 If your car is older it’s a good place to start. It’s surprising how much build-up can happen in a radiator and cooling system. Especially with aluminum oxide and general debris.
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