Where does your temperature gauge sit?

The temp gauge indicates when it's cold, when is it sufficiently warmed up, and then if you start approaching the "danger zone". That's about it. It doesn't budge when you are pushing it up a hill, when the engine is certainly warmer than normal.

As was said earlier, the temp gauge doesn't report "true" temps because people are dumb and would freak out if they saw the temp moving around (like it actually does).

I wonder if it slowly rises when warming up because the needle is purposefully "slowed down", like the gas gauge. When I fill up my tank, the needle doesn't just pop back up to full when I start it back up, you can see it slowing rise, even though, as far as the truck knows, it instantly got more fuel since the last time the ignition was on. I think that's so when you go around corners, go up or down hills the gas gauge doesn't move and give you a false sense of your fuel level. I don't really know that, it's just a theory...

 

In all honesty the actual temp doesn't really matter anyway. Unless you're the engineer that set the specs for what temps it should be running at, the "is it fine" or "is it not fine" is sufficient for most people.

I kind of cringe when I see all the specs some people actively track with their scangauges or whatever. That's a lot of info to keep track of when you're driving... Then you start suffering from information overload. You focus on that 10 degree swing in temp like there's a problem.

On my '17 4Runner, I set up my OBDII/Torque Pro to track the trans temp, so that I can see if/how much the trans temp varies while I'm towing my travel trailer. I've been keeping track of the temp during normal city driving, then when I tow the trailer this weekend I'll see how much it changes. I'm not too worried about the absolute temps, I just want to see changes. If it changes enough, I'll consider a trany cooler like I have on the Tacoma.

 

OK I'll buy your theories but, then how do you explain the occasional fluctuations from a bit below half, up to a bit over half suggesting as someone said above, the 'stat opening etc.? That to me, is the gauge actually reading temp. in real occurrence. Yeah I agree it likely is not "accurate"-the lack of numbers proves that out.

 

I can just about guarantee it's not reading the temp directly. It's just indicating what the ECU tells it to. So it's more like it's reading a "filtered" temp based on programed criteria set by the factory engineers (just like the idiot lights).

I can't say with certainty that mine has *never* moved, but every time I've looked at it over the last 14+ years/100+k miles, it's been in the same position. I can't really comment on why yours seems to fluctuate more than mine, except that maybe either it's because it's from a different model year, hence different programming criteria, or your driving style causes the temps to fluctuate outside of that "normal" range, and hence the needle moves more than mine.

EDIT: again, these are just my theories, I'm no Toyota engineer...

 

Well you sound like you know more about this stuff than I do. Probably it's true about the different model year and parameters, but as far as my driving style, no. I tend to read my dash often and that needle has moved up and down again when I'm stopped at a light. For what it is, it is actually "reading" temp...albeit in a rough fashion.

 

I can certainly make it appear I know what I'm talking about, lol...

It would be interesting to find out more about the programming parameters to figure out exactly why, but it's not like any of this would be concerning to me anyway. As long as the temp doesn't climb and stay there, and start approaching the red, I think we're all good in the hood.

 

The temp gauge on my 2.4 gradually comes up to halfway as as the engine warms up.
Once there at half, it's stable.
Breadcrumbfail, if you want to test the gauge. Go buy another sending unit and attach the stock lead to it. Attach a good ground to the threads. Place sending unit in a cup of boiling water from the microwave (212 degrees) Even allowing time to get from the microwave to the truck, the gauge should still climb.
I'll have to try this on my truck and see : )
At least that should tell you HOT VS NORMAL.