Heater problem?

[Plays_with_Toys]

Well I had my clutch done about a month ago, and he pulled my motor in order to do this. This may or may not have an effect on your answers.

Ok, so now that it is colder, something strange is happening with my heater. It'll blow cold at start up (thats normal), as the motor warms just a little it'll blow hot, and continue blowing hot until the engine reaches normal operating temperature and then it just blows cold air. This has happened twice. I shut the motor off for a second, restarted it and it blew hot again, but not quite as hot as before and definately not as warm as last year. Doesn't matter if I have it on recirc or not.

What could this be? Thermostat going out would do the same thing, blow cold air, but that would also not let my engine warm up (if stuck open), and it would overheat (if stuck closed). I have had no coolant issues (the needle is always in the middle). Ideas?

[Wiscon_Mark]

heater manifold is b0rked?

It's a funky sounding problem.

[kfy1232]

well first you should check the coolant level, the condition of the coolant and the thermostat, if those are all good then feel the heater hoses with the heat on full blast and the car running all warmed up, both hoses should be too hot to keep your hand on. if one hose is hot and one isn't then you might have a clogged heater core. another possibility is that the blend door actuator is not functioning properly.