Heater on 2005 Sierra does not work
I bought a 2005 Sierra SLT with 42k miles on it on Saturday 2/20/2010 from a used car dealer. The truck looks and runs great, ran a car fax and car check and it was rated at 93 on car check. The truck was fine until I ran it through the car wash today and now it wants to blow cold air and the heater will not come on. The temp guage is showing normal, could this be the heater core?