I took my 01 S4 to my trusted mech today...no heat...thought it was the thermostat but he reported a clogged heater core. They are soaking solvents with the goal of breaking the clog which he reports works sometimes for a week....sometimes for a year. Anyone ever have this problem...? Any successful cures? The car has 133k so I'm less inclined to replace the heater core as I was told that it was big $ to pull the dash. Thank you.

 

try pulling the heater core hoses under the hood and run hose through it, it worked for my buddys audi 90.

 

Yeah, I can usually unclog them by running a hose into *the outlet* of the heater core. The clog isn't going to want to get pushed further into the core, push it out of it.