Brief coolant smell on first start

[mmurphy77]

My 2015 just turned 43k. Lately and only occasionally I get a quick whiff of coolant when starting my vehicle in my garage and I'm outside the vehicle. It seems to waft from under the vehicle (definitely not the exhaust) and dissipates immediately. I don't smell it any other time when starting. There is nothing leaking that I can see (completely dry top and bottom) and I have no coolant level loss. Could the cap on the overflow bottle be bad? My friend's Ford Edge had a similar problem and he said that fixed it. I'm skeptical.

 

[1000MPH]

The coolant reservoir cap is designed to release excess coolant. I found my cap would leak a bit and I’d get a little whiff of coolant after a visit to the dealer where they would fill to the full line or above when cold. I haven’t had that smell for awhile but got it again recently after I did a coolant flush and slightly overfilled the res. Or maybe you’ve got a problem.