No laughing, but I have noticed that when I first start the car (2008 IS250), the exhaust has a sweet odor to it. Almost the old ethylene glycol antifreeze sweet smell. Now, I'm not loosing coolant or anything from what I can tell, plus the new 100K life Lexus coolant doesn't seem to have the old Prestone Antifreeze odor anyway. But was interested if anyone else had noticed this, especially if you have a garage. In searching the forum, I've only been able to find complaints of the sulfur odor in the exhaust. Always use 91 or better premium, usually Shell. Could it be the additives in premium fuel? Maybe Glade makes exhaust deodorizer.

 

I'm getting the same thing, but with my motorcycle. I'm really beginning to think that it's the byproduct of burning ethanol not coolant.

 

It's the raw fumes that have escaped due to the cats not being warmed up. Once the cats are hot, they can trap it better.

Just hold your breath until your car is warm, should help.