Car smells awful, and now there is no coolant.

My car has been smelling bad for the past week. I figured the smell was coolant. It seems to be coming from the A/C. Also, when I was coming home from school tonight, engine temps started shooting up. Luckily I was able to keep moving and get the temp to drop back down.

When I got home, I looked in the radiator and couldn't see any coolant, but I also can't find it anywhere in the engine bay or under the car. Does anyone have an idea of what could be going on?

Since you said it is comming from the A/C (which I assume you mean the vents inside the car) And your coolant level is low.. I would say your heater core is leaking or heater hoses. Do you notice any wet spots under the dash area where coolant would be leaking out?

Yep, it's the heater core. I'm going to replace it tomorrow. Thanks for the reply.