I own a 1999 ford f-150 4.6 liter 4x4...that i just recently flushed the cooling system due to the heater not blowing very warm air......

every since i flushed the system, whenever i turn the heat on, i get a strong smell of anti-freeze, and my windows fog up so bad that i have to wipe thewm off with a cloth. I have looked for a leak, cannot find one. I have checked inside floorboards , all are dry...... could this be the heater core, and why would it only do this after flushing? the engine never overheats......

 

More than likely.

There's been a lot of discussion about replacing heater cores, suggest you do a search. These aluminum cores commonly fail b/c of internal corrosion & flushing can open up pin holes. Failure to change antifreeze is implicated in the corrosion.

 

just dont breath that stuff in, i cant imagine it is good for you

 

My 85 f150 was pretty bad about the heater core going out. Driving around and breathing that anti-freeze in gave me the worse headaches ever. When it would go out it did the same thing, it cause the inside of the windshield to fog over. It also leaves a film on the inside.

 

Definatley the heater core... just did mine on a '97 f150....not hard...not fun...pland on spending 6 hours doing it yourself.

 

Thanks For The Reply's Guys.......

Guess I'll Be Replacing The Core Come This W/e......

 

This might help. Good luck!
http://my.voyager.net/~sscully/F-150...50_Exp_002.doc

 

Definately the heater core. $100 in parts and 6 to 8 hours of labor. Not hard just time consuming... Just did one 3 months ago.

 

LOL....Ah, the dumb stuff we do when we are young. Reminds me of the times me and my buddies would drive down to see Jimmy Buffet in Cincinnati and the car leaked so much carbon monoxide in the cab that we had to hang our heads out the window the whole trip. Who would have thought that was bad for you?...