1994 Cougar- Lukewarm Heat Inside
1994 Cougar, 109000 miles
I just put a new heater core in; took me and a friend all day, too. Got everything put back together with no leftover parts or screws. All wiring harnesses are plugged in, where they belong.
Now, with the engine warmed up, it's giving merely lukewarm heat out of the vents: floor, dash, and defroster. I thought it might be air in the lines, and had to add some coolant a time or two as the air worked its way out. But I'm still not getting real hot air in the cabin at all.
The vacuum lines look good; they're not loose or pinched.
This has manual heater controls, and I happened to notice there is no difference in air temp when I turn the knob between full cold or full hot. It blows only lukewarm air on any setting. I have a hunch it might be the blend door? Blend door actuator? Temperature blend switch? I'd rather not pull the dash again, but I will if I have to. So I'll start with the easy one first- Is there a way to test the switch? I see it has 3 wires on it.
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