I have a 1985 Jetta Diesel 1.6 n/a with a 5 speed and a/c. I just got the heater controls fixed where the fan blows with all 3 speeds. When I turn on the controls for heat, it barely comes out warm. I've flushed out heater cores before with some success and am wondering if these jettas generate enough heat. The a/c works great if that helps. From what I see, pulling the heater core is not one of the things I want to do.