A/C blows hot air after replacing heater core (1996 GT)

ninman8

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I finished replacing my heater core yesterday (big job, you have to take out the dash) and while I was testing everything out the heat worked great (yay) but now, when I turn on the a/c, the system still blows hot air as if the heat is still on. What could be broken? Is it something in the engine bay or something I might have messed up when I took out the dash?
 

07GtS197

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Make sure everything is hooked up to the back of the ac control unit. There are two cables that come off the back that control the blend door. Most likely it’s not attached on one end or the other.
 
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ninman8

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Make sure everything is hooked up to the back of the ac control unit. There are two cables that come off the back that control the blend door. Most likely it’s not attached on one end or the other.
What do they look like? I have an sightline on the back when I remove the radio and it looks like everything is connected correctly. Which ones control the blend door?
 

cobrajeff96

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I was going to say maybe the blend door cable didn't get hooked up or it got snagged on something during the re-assembly maybe. Can't mistake it, it's a stiff cable connection. And then there's the vacuum block with the little hoses on it.
 
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ninman8

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Has a black sheath and it attached right to the back of the control panel. It's the super stiff cable.
I didn’t see anything like that last time I looked. I’m going to go back and look again in a few minutes though. Maybe I can post some pictures
 

cobrajeff96

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By cable, I mean mechanical not electrical. It's a tether inside a sheath, hooks right up to the center temp control and leads to the blend door beneath the dash.
 

07GtS197

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Pull the whole control head out. It’s the white piece with the black circular gear. It may not be attached at the other end.
 
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ninman8

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Pull the whole control head out. It’s the white piece with the black circular gear. It may not be attached at the other end.
How do I pull it out? When I was removing the dash I couldn’t get the whole thing out even after a lot of effort
 

07GtS197

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How do I pull it out? When I was removing the dash I couldn’t get the whole thing out even after a lot of effort
There are 4 bolts that hold it in place. It should pull right out after they’re removed.
 

cobrajeff96

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From what I've encountered any time I pulled my dash, it's difficult to detach the cable drive on these things but I guess you never know. Your temp knob is the pinion and the black gear is the ring. Right off of that assembly is the cable to control how much heat or cold is realized. I'm betting the cable itself was just routed too sharply when the whole dash was remounted or got snagged on something sharp like the dash frame itself.
 
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ninman8

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From what I've encountered any time I pulled my dash, it's difficult to detach the cable drive on these things but I guess you never know. Your temp knob is the pinion and the black gear is the ring. Right off of that assembly is the cable to control how much heat or cold is realized. I'm betting the cable itself was just routed too sharply when the whole dash was remounted or got snagged on something sharp like the dash frame itself.
Thanks for the help! I’ll see if I can mess with it this afternoon. I’ll keep you guys updated
 

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