Hello again,
during our last trip we drove over some high passes here in CO and on one occasion we got stuck behind a bunch of slow cars near the top of the pass, resulting in 10 minutes of crawling uphill in 1st and second gear.

The engine got pretty hot and we noticed a smell that reminded us of a badly adjusted car - so we thought it was from a vehicle in front of us. However it soon became clear that the smell came from our car.

What does the orange coolant smell like when it's burning? Does it smell a bit like unburnt fuel or badly adjusted motor emissions?
The reason I ask is that I remembered the low coolant light coming on last fall and I had filled the black reservoir to the bottom of the filler neck then. I checked it this morning and it was about 1-2 inches below the filler neck. No warning light as of now though.

Could we be losing just a little coolant when the car is hot and it gets burned somewhere on the engine?

What else could cause such a smell?

Any advice would be appreciated.

 

Burned coolant has more of a "sweet" smell. It does not smell like bad emissions or gasoline.

However, what you describe sounds exactly like a coolant leak. It is a closed system, so if you have to fill up the reservoir it is because you have a leak or air in the lines. Most likely it is a coolant leak.

The common places for these to leak are conveniently located near hot engine parts and often burn off before they can be seen or create puddles. Search the threads to find the usual spots, but start with all the hoses in and around the expansion tank. Look for signs of dried coolant.

 

That's what confused me. I expected the sugary smell of coolant. None of that. I read somewhere though that the DexCool smells different???

 

No, it smells the same.