I live in high altitude 3000 Ft wish, and its also hot 90 degrees F. Ive noticed this whistle before but it seems to stop.


Today after driving back up the hill and the Camry was whistling, kind of like a tea kettle but not as pronounced. Coming from the front of the engine.


Has anyone else come across this whistling?

 

It's pressure cap. Radiator cap.
What that cap does it is not just keeping coolant inside. It's also building up pressure inside the system, allowing coolant temp to go up by about 40 degrees. Fluids under high pressure have higher boiling point, so by doing this, it raises coolant boiling point to keep engine run warm.Then excessive pressure is bled into the expansion canister.
I bet because of the high altitude=lower barometric pressure, cap bleeds pressure somewhere with a whistle.

 

Alright, ill head down the hill and see if it does the same thing at the bottom.


Thanks ukrkoz for the insight. My wife is from England so we can't decide what temp to use C or F, lol.

 

It does not matter. Brits can remember several numbers in standard, just for reference. Your ICE should run at about 190 F. Pressure cap allows coolant to reach that temperature. It's the only pressure controlling device in quite simple cooling system that actually "moves" as pressure changes. That sort of points towards it right away.

 

You need to let us know a little more about the car. Is it whistling "God Save the Queen" or the "Star Spangled Banner"?

 

Ohhhh say can you whistle, by the dawns early.....

All jokes aside. It only does it every so often. It's rare but it's there.

 

It's like my sexual life. Twice a year but it's there.
Wife's Rx300 whistles at HWY speed above 55mph. Through rear tailgate weatherstrip.
It's not big expense, so maybe change radiator cap? Or, clean current one? Sometimes there's crystalline build up on seals.