On my 1998 volvo s70 the floor is wet with coolant on the drivers side and when using the a/c you can smell freon and you can see a white fog coming through the vents

check your heater coil

Don't remember exactly , but I think it could be done without dash removal.
It's done from driver side footwell area , tight but possible.
You have to take out lower center consol side cover , next to the accelerator pedal and roll the carpet out of the way, and you will see the heater core case. Remove cover on the case (some have it on the side , some on the bottom).Two pipes going from firewall to the core have to be disconnected before core removal (will leak coolant , have some rags on the floor to absorbe it).
Slide heater core out , put new one in gently as the accelerator pedal is on your way , try to avoid damaging core a lot.
Always replace heater core pipes o-rings.

Most of the time smell coming from heater is do to a heater core starting to leak, does it steam up the windows when the heater is on? is the passenger side floor wet? can you describe what it smells like musty or kinda sweet? well will be waiting to hear back from you thank you ,

If it smells sweet it is coolant and this is a sure sign your heater core is leaking. The only fix is to replace it.

check radiator for leaks and thermostant might not be working alo check transmission fluid some times radiator fluid will mix in with transmission fluid since transmission fluid lines run throug radiator

Sure sounds like the heater core, the only other thing would be some time of leak that is raising the moisture in the car is the floor board on the passengers side wet? If not look toward the heater core.

If the car is a manual its likely to be clutch fluid from the master cylinder.

Cheers John

Your heater core is leaking. The smell and smoke is from the coolant evaporation.

from he Popular Mechanics site if the smell in your car is like maple syrup:


(1) SMELLS LIKE: MAPLE SYRUP
WHEN: After the engine has warmed or possibly even after it's shut off for a few minutes.
THE CULPRIT: Coolant containing sweet-smelling (but toxic) ethylene glycol is leaking from somewhere. It could be coming from a radiator or heater hose, a failed intake manifold gasket or cylinder head. It might be coming from a leaky radiator cap or the radiator itself, especially if you smell it outside the car. A strong odor inside the passenger compartment probably means a bad heater core.

I just saw fog lights on e-bay for about $125 - $130 + shipping.
So the relays are there? I have not checked not car yet. I was told fogs need a "J relay" and a "white relay with green feet" under the driver's side knee bolster, and a "gray relay" at the fuses. Please let me know if you have part numbers in case I need to order them. (Maybe I will try a donor car from a salvage yard). Good luck.