The windsheild in my car won't un-fog no matter how warm the vehicle gets, what could it be?

Question

It almost seems like the moist air that keeps fogging it up is coming from the heating system itself... Just started doing it all of a sudden today. Also, should be noted, that it also smells kinda like oil in the cab, it's a new smell and I'm not sure if it is a related issue.

The oil smell is not that of burnt oil, but of fresh oil.

I rain-xed it about a year and a half ago, on the outside, but have never done the inside of the window, where this fog is.

Answer 1

Most likely you have a bit of a leak in the heater core, and the moisture is blowing onto the window. The smell is what gives it away.

Answer 2

can be the heater core or hoses that lead to it don't know just were you live but sometime in the humidity place if you roll window down a little it will push out the moister in your car the smell of oil an not the sweet smell has me thinking your car got very hot an you may have a head gasket gone too if you find water on the rug under passenger side your core or hoses have to be replaced . look around for a good tech. less you know you can repair your self

Answer 3

Sounds like a pin-hole leak in the heater core.This will cause the funny smell and the condensation on the inside of the window. Basically, the best solution here is to replace the heater core.

Answer 4

sounds like your heater core is leaking antifreeze into the heat duct. this is a common problem. look on the passenger side floor for any wetness. sometimes it will leak out of the heater assembly sometimes not. be sure to check your coolant level! by the way antifreeze has a kinda sweet smell

Answer 5

You didn't say what kind of car it was but iam betting that it is not oil from what you describe you have probally have a heater core gone bad dont run it to long coolant loss is devistating to the newer motors

Answer 6

sounds like to me you may have antifreeze inside the car from the heater core....antifreeze is usually a ethylene glycol base and thats feels alot like oil,sometimes has a sweet smell .heater cores usually fail and cause this

Answer 7

getitfixed certainly has a good recommendation. I wonder if the smell you are describing is due to an air conditioning leak and what you are smelling is the refrigerant/lubricant. When the defroster is selected on any modern car with A/C, the compressor kicks in to dehumidify the air. If the A/C charge is too low, the defroster is markedly less effective.

Answer 8

sounds like your heater core sprung a leak ,it will send moisture into the car and ends up on the windshield through the defroster vents (smells kinda sweet???)

Answer 9

I have had that problem before with my Ford. Try running your air conditioner instead of the heat on defrost...I know that sounds wierd, but it worked for me. After it runs for a time, you should be able to keep the fog off by just using the reg. heating...direct it on the floor. I think it has to do with the condensation inside the vehicle.

Answer 10

Heater core.