Heater Core 2000 GMC Jimmy

I have a 2000 4X4 GMC Jimmy. I am smelling coolant from the vents on the inside but, I have not found any leaks anywhere. I have heat coming out of the vents after the engine warms up. I have already changed the radiator cap. What else can be making me smell coolant?
TOTALLY CONFUSED!!!

I have a 2000 4X4 GMC Jimmy. I am smelling coolant from the vents on the inside but, I have not found any leaks anywhere. I have heat coming out of the vents after the engine warms up. I have already changed the radiator cap. What else can be making me smell coolant?
TOTALLY CONFUSED!!!

By now your heater is probably blowing out anti-freeze all over the inside of your windows, your heater core more than likely has a leak

Heater core needs replaced...

I have a 2000 2D GMC Jimmy with 88,000 miles. The easy fix that worked for me is putting Barr's Stop leak in the radiator. It fixed my leak, and the smell is almost gone now, but it took two-three months for the smell to go away, and I still smell it very faintly every once in a while. Someone told me a sure way to tell if it's still leaking is turn on the defroster, if it defrosts your winshield, it's not leaking, it if stays fogged up, you have a leak.

Stop leaks are the worst thing you can do to your cooling system. Do not do that to your cooling system! You're only putting a bad bandaid on a problem. If you're gonna fix it, do it right..

ps. yes the leak would be in the heater core. if you do add barr's stop leak, make sure that you run the truck for at least 15 minutes after adding it.