Nappeal

With the now constant use of the heater, I'm noticing this off-on again odor, in the cabin, which is either coolant or wiper fluid. Its a bit sweet, but honestly smells fishy, and usually comes exploding out of the vents when I do a hard acceleration, lasts just a couple minutes, but does not happen all the time, and very infrequently. Heater fan blows out nice warm air, but regularly all the windows will fog up, even when its just me in the car on a nice dry day. No puddles on the floor board, no fog or mist coming from the vents, but I've got a constant film on my windshield I suspect is from coolant. Occasionally I will hear what sounds like water slopping from behind the center of my dash when I accelerate from a stop. I just had the oil changed=all the fluids were topped off so I don't know if I was low on coolant, and I'm not noticing any leaks. Over the summer with A/C, the HVAC seemed to drain a little more than I thought was normal. Any thoughts? Its so infrequent, but jeeesus it smells horrible when it does comes in , and if it needs fixed it needs to get done now. My mechanic literally just moved across town and I haven't found anyone trustworthy yet, thanks!

ruley73

If you don't see any leaks in the interior, the heater core is probably fine. Make sure you occasionally clean the inside of your windshield. A windshield with dirt & grime on it fogs up a lot easier than one that is clean. I would check your cabin air filter. It probably needs to be replaced.

You could also have some smelly mildew on the evaporator core. This typically smells really musky or like wet sweaty feet. Get a small can of Ozium and with the A/C on full blast, spray a generous amount of it in the inlet vents in the cowl under the windshield wipers. This has rid of the bad smell for me. The Ozium I use is the plain stuff with no added scent (i.e. new car smell, strawberry, fresh air, etc.) It has a fish bait kind of smell to it, but it is temporary and goes away within a few days. It kills the musky smell almost immediately.

The slopping sound from the center of the dash is just coolant flowing through the heater core and is perfectly normal. Our Equinox makes that sound too, but I can't hear it unless the radio & fan are turned off.

cleveland63b

Have you had to top off at all? The sloshing isn't normal it means the system isn't completely full, fogging windshield and coolant smell are the top 2 symptoms of a leaking heater core. You could pull the carpet back on the passenger side and check for moisture or even the evaporator drain for coolant traces but going off the symptoms I wouldn't be surprised at all if the heater core is leaking.

tech2

I've done maybe 15 to 20 heater cores/ blend door repair on nox's. the coolant will stay contained in the hvac box. When you open it up, the foam around the core will be soaked and the bottom of the box will be wet.


you sure have a lot of symptoms of a leak.


don't know if this will show anything but maybe remove the blower motor and inspect inside the box with a videoscope.