re: Noticed my engine temp is starting to waiver

quote:

---

If it does it at idle

---

You just gain the luxury of being able to sort it out in your driveway instead of needing to load the engine to do it.

Let it idle, put the AC on full maximum blast, and see if it still happens.

First thing you need to do is verify that the coolant temperature is actually unstable, and it isn't just a gauge problem. Not the easiest thing to do, but you can slide a thermocouple between the coolant out house and the neck and re-tighten the clamp and it'll seal good enough to sort that part out, or just figure out a way to read it digitally.

If you want, I could mail you my OBD2 scanner which you could use to read all of the engine parameters on the can bus network. I imagine coolant temp is on there and maybe coolant pressure as well.

You could buy yourself one for about $50 for a very good one. Essential tool for anyone to have who is going to do any diagnostics on their own modern vehicle

Well, I lied. The one I have is actually $140. I like it a lot though

LINK

Alternatively, this would PROBABLY tell you most of what you need to know

LINK


I do recommend getting the first one though if you can swing it. I know for sure that is a very capable scanner with a very good companion app, and you'll have it for every car you own from here on out. I'd trade in my cordless impact for it if I had to. It's more useful.

quote:

---

the AC on full maximum blast.

---

This should make the fans run on high as I recollect.

You might be low on coolant and/or need air purged. Low level can cause air or a "bubble". Have you noticed any leaking? I suggest adding about a half gallon and then watching it again.

Thermostat sticking is another cause though.

So it does not run hot or waiver at all when parked. It spikes on increase RPMs, remains pretty stable when running at a constant speed/RPM. I am thinking the fans are not hitting high gear, this is going from memory but I think the fans use to hit high speed when parked and it was a noticeable change in noise. They are not changing speeds at all when parked and the AC blowing at max.

I got the code reader in but haven't had time to use it.

Downshift - will it be able to show the power draw or some other way I can see how the fans are running?

Both fans run when I crank up the truck.