Do you have air in your system?

 

I don't know, how do I tell? I've not noticed anything unusual from the engine bay. Would air migrate upwards into the overflow tank over time?

 

Boy, the flash really reveals just how dirty my engine bay is. https://i.imgur.com/X4DncR6.jpg

I actually have to check the manual now and find out if that's the proper level for the coolant. Maybe it's low?

 

When cold, the coolant level should be at the middle seam in the overflow tank per the service notes.

 

Thanks. I found my service notes and brought the level up to the proper spec, which is 10mm to 25mm below the seam in the tank. Hopefully that resolves it.

The notes also recommend a 4 year flush, which I'm probably due for.

 

I’ve had similar issues with coolant. It’s insanely hot here in the desert Southwest. Thus far my engine is running at normal temps. Fans come on and go off but I get a very faint coolant smell when I stop. Remember it’s well over 100 degrees here during the day. At night when it’s cooler I don’t smell the coolant.

Nevertheless it seems I’m losing coolant. I think replacing the cap is the first order of business. Any other thoughts? Also will I be able to purchase the cap at Toyota?

 

Did you ever experience the situation where it'd engage the rev limiter at a lower-than-normal RPM, even when the temperature gauge read a normal temp?

 

No, nothing like that with the rev limiter. It revs as far as I want to take it but admittedly I rarely let it go much over 5000 rpm. I’m a rather conservative driver.

 

Get a code reader and see if there any code or un set whaddayacallits

the low rev limit means it is unhappy about something

Consider the possibility that the two things are unrelated

 

I went to Advance Auto and I scanned the codes. It wasn't throwing any, and it no longer is rev-limiting me at 4500 RPM. I suspect the coolant was just a bit low. I'll watch out for that and see if it's leaking. Thanks for the help

 

I went to Toyota today to purchase a replacement cap. They said there is an updated one which I bought $29. I’ll keep you posted on whether or not this solves my faint coolant smell

 

Update: the new cap seems to have solved the problem. No more faint coolant smell. The car came up to temperature fairly quickly (101 degrees outside) and it stayed glued to the center of the gauge bar despite stop and go traffic. Cooling fans never came on either. It was interesting the service advisor at Toyota said the caps should be replaced at 2 years. Again he indicated the caps have been upgraded. Photos are of the cap as well as the packaging.