[Tom-Accord]

Hello,
I have a 2024 Accord with 300 miles on it. The weather has just started to turn cold and I've noticed a sweet smell coming from the heater supply. The intensity of the odor comes and goes and oddly, the smell from the driver side, right hand dash vent has the strongest smell. It is not really detectable in the other 3 dash vents. You can also detect the smell in the defroster mode. A Honda dealer ran a 30 minute/16 psi pressure test on the coolant system and detected no issues. They also used a flexible scope to inspect the heater core with no leaks found. The next step would be removing the dashboard to better inspect the heater core, but I would be liable for the cost unless a leak was found. I'm also hesitant deal with any potential downstream, out of warranty issues with removing/replacing the dashboard (rattles, electrical issues, etc.). The tech stated that additional customers have complained about this same issue - just posting this to determine if there are others out there with this symptom.

 

[audio.bill]

I also noticed a slight smell of antifreeze from the vents after taking delivery of my 24 Accord Touring Hybrid, so the dealer checked it and found no leaks. Happy to report that the smell went away completely over time and haven't had any related issue now over a year since delivery.

 

[jackpine]

Even a tiny seepage will give you the smell you describe. I'd continue to monitor it and if it doesn't go away fairly soon. take it back to the dealership for a more thorough check.

- Jack

 

[Tom-Accord]

I also noticed a slight smell of antifreeze from the vents after taking delivery of my 24 Accord Touring Hybrid, so the dealer checked it and found no leaks. Happy to report that the smell went away completely over time and haven't had any related issue now over a year since delivery.

Thanks audio.bill - that's comforting to know!

 

[Tom-Accord]

Even a tiny seepage will give you the smell you describe. I'd continue to monitor it and if it doesn't go away fairly soon. take it back to the dealership for a more thorough check.

- Jack

Thanks jackpine, I am definitely planning to monitor the coolant level and look for any signs of leakage until it is resolved.

 

[The Hard Truth]

Probably the " new" - hopefully it will clear up with no future issues.

 

[WMGwizard]

It is not uncommon for some initial "seepage" to occur as the new parts require a few thermal cycles to form a complete seal.

It only takes a couple of drops to create an odor and may take some time for the liquid to evaporate and the odor to dissappear.

 

[KRK]

I also have a 2024 Accord Ex 1.5 and noticed over the past couple of days, when using the heat, I have intermittent coolant odor. I have checked the coolant level at the radiator and reservoir, no loss of coolant. No leak on the interior or fogging of windows. Also confused by this issue

 

[dwagjohn4]

2025 Honda Accord 5 miles and I noticed it the same day I left the dealer.

 

[Tom-Accord]

2025 Honda Accord 5 miles and I noticed it the same day I left the dealer.

Thanks dwagjohn, that makes 3 people so far with the same issue. I'll report back here if the smell goes away, please do the same.

 

[Miker]

You may want to investigate the cabin filter. I was able to attribute the similar odor on my 2013 when purchased new.

I also notice a "sweet" smell whenever I replace that cabin filter. It's not that the filter is being contaminated with coolant since it's on the other side of the core, but when ever I remove the filter from it's protective bag a strong chemical smell permeates the cabin for a few weeks.

Worth looking into to allay your concern for a heater core leak.

 

[apollo]

I have a new 2024 and have the same odor. Going to the dealer on Dec. 6th. Will let you know if they find anything.

At the suggestions of some others I took the time to take out my cabin filter. After I did this the smell went away.

 

[Tom-Accord]

Thanks Mike, checked the cabin filter with no issue detected. Tom

 

[Accord_Mike]

No coolant smell from mine. The only smell is that nice new car smell which I love so much. Since I don’t smoke nor eat in my car, I hope it lasts a long time.

 

[KW2004Accord]

No coolant smell from mine. The only smell is that nice new car smell which I love so much. Since I don’t smoke nor eat in my car, I hope it lasts a long time.

That "new car smell" is the results of off gassing from the plastics & adhesives (not good for the very young & elderly) - https://www.caranddriver.com/features/a36970626/science-new-car-smell/

 

[mtts60]

Who cares if it's not good for you, it smells good. Much like wood fire smoke.