I’ve had this car now for 10 days and it seems every time I drive it the smell of antifreeze keeps getting worse. Either that or it’s more persistent. The overflow reservoir is about 1/4 inch below the low mark but it was there the day I bought it and it hasn’t moved. I marked it. I have seen lots of posts in the forums about this issue with earlier years and there are a couple I have come across about the 8th gen. I just wanted to see if there were any updates anyone may have about this issue. I have looked under the car and all over the engine and checked the hoses, etc.... I see nothing indicating a leak of any kind. It’s a bit too strong of a scent to just rule it out and leave it alone....

 

This summer my wife hit a deer and broke the radiator and some hose connections. After it was all fixed with a new radiator the system was pressure tested, passed, and everything worked as designed except for the smell of coolant whenever she pulled into the garage. Never had to add coolant but the smell was always there after engine shutdown. After a couple of months the smell went away and never returned.

My theory on this coolant was spilled onto the engine and elsewhere during the collision and replacement and dried up. When the car is run and heats up the dried coolant releases vapors that you can smell and goes away when the car cools off. Eventually all the spilled coolant is gassed off and there is no more smell. There was never anything wrong as there was no evidence of leaking or coolant usage. Maybe this is your situation.

 

Maybe.... perhaps there was hose replaced but who knows?? It has 44K miles and is in great shape. I don't see any evidence of any mechanical work but the engine is too clean to really tell. I spent at least a 1/2 hour checking it out and I found no evidence of anything leaking. The dealership I bought it from said there was nothing mechanical done to it and I believe them at this point. I just tried googling antifreeze smell with Maxima and there were quite a few hits so it got me thinking there might still an issue. I'm 5000 miles away from the drive train warranty expiring so I'll drop it off and let the dealer check it out.

 

Since I've owned this car the coolant overflow has gone down at least a 1/2 inch and I keep getting the smell of antifreeze. It smells like antifreeze that is being "burned off" such as leaking on a hot exhaust pipe or something similar. I did notice the burnt antifreeze smell in the reservoir when I opened the cap.

I took it to the dealer and I took it to a local mechanic. They both pressure checked the system and found no evidence of leaking. So at this point I am at a loss. Its great having people in the car with me notice the same thing and trying to explain there is nothing wrong.

 

Since day one with only 30 miles on the odometer , when I got to my garage I could smell the coolant. Fast forward almost 2 years and I believe I got used to it. Took it to the dealer twice and they did not find anything. I have noticed that the smell it is not as bad as when brand new but there it is still there....

 

You have nothing to worry about. My back-then new '07 Altima had that smell, and from the first warm day with my then new '17 I had that smell. With the '07 I found a slight powdery, lt. blue color, and sometimes damp area around the cap of the overflow container. Although I could never find where the canister "boiled over" from excess radiator blow-off, I did once catch a lot of antifreeze drops adhered to the inside of the canister after idling the engine on a hot day for over 15 minutes. Just like the Gen 8's, that overflow system is not a "closed" system containing a pressurized overflow container cap, so I suspect that every time the radiator gets a little hot and blows/spurts into the radiator overflow tube and into overflow container, a bit of that atomized antifreeze vapor reaches your nasal passages. And yes I know, even on a very cold day, where one would think the overflow system might be inactive, the process still does occur, and thus the antifreeze aroma. I agree that there is a slight loss of antifreeze (maybe 1/4" to 1/2" over a year), but that is to be expected with an "open" overflow system. Yep, I have never detected antifreeze weep anywhere on or near the engine since the Gen 8 was new........ so no problem. I think it is the nature of the beast. Dealer has checked also a few times. Nada. I notice that if I place my personal smelling orifice very near the radiator pressure cap I always smell that smell even though everything is dry as a bone. For the record my Gen 8 has never shown signs of any antifreeze weep around the overflow container cap like it did with the Altima. Kinda perplexing for a new owner.

 

Same experience. First year was more noticeable. Never added an ounce in 3 years.