since last winter ive had anti freeze odor along with fog on windsheild for minute or so when turning on defrost . when i look in the engine compartment at firewall where heatercore hose goes through theres absolutely no sign of leak , its dry and theres long term oily dust on firwall around hoses . but still i messed around with the hose clamps there at wall putting them up closer to firewall in effort to get a better seal possibly and now it seems like im getting alot less fog on windsheild plus less anti freeze odor . is it possible a bad seal of hose at heater core pipes in engine compartments allowing water to get into heater core box , but not drip on exterior of firewall , and cause my fog / odor ?

if read this and have opinion ide appreciate quick reply as i bought my heater core and am going to start project tomorrow or sunday because winters approaching and busy with work so my windows now

 

Replace the heater core. If you are suspicious of the seal with the hoses, get new ones. When you have it apart, leaks should be obvious.

 

i had a similar problem and after getting the core out found it to be the spring clamps. I would try some new clamps for a while before doing that much work.