2025 RX 2.4L turbo, non hybrid. I notice on the highway that the engine temp varies sometimes as much as 30-40 degrees. Specifically going down to 180F then climbing back to 206-208F. Today I noticed it get as low as about 170F. I also sometimes hear the cooling fans kick on and then off, but I don’t notice a reduction in temperature. Anyone else experienced this? Is this normal?
Coolant reservoirs are at the full mark.

 

mine hovers around 206-208 most of the time after warm up

 

Mine is routinely between 200 - 210, spending most of it's time in the middle of that range.

 

What setting have you guys enabled to get those temperature readings?

Ours only displays the BARS to the left of the instrument. Is it because I'm using METER 3?

 

I'd have to find exactly how I did it, but there is a setting to select what you want to display to the left and right of the main meter. I had an elapsed time clock there when I took delivery, which was kind of useless, so I picked one that displayed the coolant temp, oil temp, and turbo boost pressure. The coolant temp is what I said was between 200 - 210.

 

Underneath that nice boost gauge are two meters on the left and right. On the left you have oil pressure, and the right is oil temperature.

 

Coolant Temperature should not vary that much after engine is up to temperature. Maybe a problem with the Electric Control valve - which replaces a thermostat.
jim

 

I experience this in my 23. My guesses were that it is related to boost, detonation, or maybe tied to intercooler performance. Or it could be that this particular coolant temp sensor is right by the coolant regulator.

 

Before I joined this forum, I was under the impression that the posters here must be very old (I mean mature) and are only knowledgeable about ancient (I mean not very contemporary) technology. I am proven wrong: instead of old geezers, many posters are geeky sages!! Hats Off!!

 

Well, since the average age of an RX owner is mid 60s and the overall Lexus owner is just under 58, you're bound to run into a good chunk of us old curmudgeons hanging around the retirement home parking lot with our RXs. A geek is is still a geek even if the mental Rolodex (for those of you who know what that is lol) may be just a hair slower than it used to be

 

The subscription to my Rolodex must have expired...either that or the card fell out and the maintenance guy at the retirement home swept it away.


PICTURES of the temp reading on the dash and detailed instructions appreciated! I'm still thinking that SOMETHING reset when our battery was replaced a week ago.

 

It's because they updated the instrument panel for the 2025 model year. I'm using OBD2 readers to get readings off my 23. Car Scanner app integrated with Android auto so it allows readings on the main infotainment screen.