Lately, when I turn my heater on after my truck warms up good I've been getting antifreeze smell coming from vents. Is this usually the first sign that the heater core is bad and is leaking? Also, I was just wondering what kind of damage can it do if I wait a couple of months before I change out the heater core. I'm just wondering since it's leaking where is the antifreeze going to wind up since it's behind the dash.....It can't be a bad leak because it's not showing any change in coolant level in the system......

 

Yes...That's the first sign of a leaking heater core..Had the same issues with other vehicles in the past...How long will it last,good question..My firebird had a bad heater core...Drove it for about two months and it started to get worse...Started to dump antifreeze on the passenger side floor...But I had another vehicle that lasted for 6 months..

Sure makes a mess on the inside windshield after a while...Had to windex the window every week to clean the oil film the antifreeze left behind...

 

Thanks.....I'm guessing my leak isn't that bad just yet. I checked and don't see any sign of any leaking on the floor board......Right now I guess the biggest problem is just the antifreeze odor inside cab when heat is on......that & the fact that the windows fog up bad now for some reason when heat is on......Thanks for the information.

 

The windows are fogging up due to steam and condensation from leaking coolant, windows will get greasy soon. I am not saying when you need to change your core, just explaining why windows are foggy.

 

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