Heater core HELP?!?!?!?!
Thread Starter
Instructor
Joined: Sep 2003
Posts: 118
Likes: 1
From: Plano TX
Heater core HELP?!?!?!?!
Anyone out ther with any experience with a heater core replacement on a C-4 (1994) with dual airbags. Heater won't generate any heat at all (thinking it's a stopped up core). Hoses are replaced & put in a manual heater control valve (and yes...it's open). Wondering how in the world to get to this thing and change it out.
Burning Brakes
Joined: Jul 2002
Posts: 972
Likes: 0
From: Springdale AR
Re: Heater core HELP?!?!?!?! (greggo's 94LT1)
Do you have Electronic Climate Control? If so, does the light flash on and off? If the light is flashing on and off it is probably not a stopped up heater core. It would be something like the programmer or in my case my Heater door motor drive gear busted, which required taking out the heater core.
Here is a photo of my door motor:
http://forums.corvetteforum.com/zerothread?id=729036
Here is a photo of my door motor:
http://forums.corvetteforum.com/zerothread?id=729036
Thread Starter
Instructor
Joined: Sep 2003
Posts: 118
Likes: 1
From: Plano TX
Re: Heater core HELP?!?!?!?! (vette92_1)
Yes. Electronic climate control. No blinking lights...Everything works perfeclty. All of the baffles move great to change ducts etc. The only thing...air just won't get hot (not even warm).
Next question...is the heater door vacuum operated or motorized? If it's motorized...cold very possibly be a gear or something.
Next question...is the heater door vacuum operated or motorized? If it's motorized...cold very possibly be a gear or something.
Thread Starter
Instructor
Joined: Sep 2003
Posts: 118
Likes: 1
From: Plano TX
Re: Heater core HELP?!?!?!?! (greggo's 94LT1)
OK...just going to pull it all aprt & (1) replace the heater core (whether it needs it or not) (2) look into the door thingie. I want to get it all taken care of whie I'm in there...and that's my final answer!
Now I just need to know how to get to the stuff. I took the bottom panel off and still having trouble even seeing everything. Is it possibly easier to take out the passenger airbag and get to it from above...or do you have to get to everything from underneath?
Now I just need to know how to get to the stuff. I took the bottom panel off and still having trouble even seeing everything. Is it possibly easier to take out the passenger airbag and get to it from above...or do you have to get to everything from underneath?
Burning Brakes
Joined: Jul 2002
Posts: 972
Likes: 0
From: Springdale AR
Re: Heater core HELP?!?!?!?! (greggo's 94LT1)
If you are not getting a flashing light than your door motor "should be" OK, however definately check it out while you are in there. It is an electronic door motor.
As far as getting to it, good luck. Mine is a 92, so I didn't have to worry about the airbag being in the way. But, I took my complete dash cap off and unbolted most of the braces under the dash on the passenger side so I could get to it.
Some have claimed they did it without removing the dash cap, but, for me I thought it was just as easy so I could see what I was doing under there.
One word of advice, do not push on that heater door to hard, if it feels pretty solid leave it alone, you can end up breaking the drive gear if you push on it very hard.
You can check the heater door movement now even before you get started tearing into it.
From outside under the hood on top of the AC box there should be a plastic wiring harness mounted on top with some wires that go to it. Take the screws out and then take a flash light and shine inside while someone inside the car adjusts your heater temp. up and down. You should be able to see the door open and close if it is working.
Good luck :cheers:
As far as getting to it, good luck. Mine is a 92, so I didn't have to worry about the airbag being in the way. But, I took my complete dash cap off and unbolted most of the braces under the dash on the passenger side so I could get to it.
Some have claimed they did it without removing the dash cap, but, for me I thought it was just as easy so I could see what I was doing under there.
One word of advice, do not push on that heater door to hard, if it feels pretty solid leave it alone, you can end up breaking the drive gear if you push on it very hard.
You can check the heater door movement now even before you get started tearing into it.
From outside under the hood on top of the AC box there should be a plastic wiring harness mounted on top with some wires that go to it. Take the screws out and then take a flash light and shine inside while someone inside the car adjusts your heater temp. up and down. You should be able to see the door open and close if it is working.
Good luck :cheers:
Burning Brakes
Joined: Jul 2002
Posts: 972
Likes: 0
From: Springdale AR
Re: Heater core HELP?!?!?!?! (SPEED750)
So I guess we're gonna pull the core instead of checking for blockage? :confused:
His symptom, sounded way to familiar to when mine quit getting cold. Mine ended up being a cracked drive gear inside the heater door motor, but my light was flashing on my control unit though, and his isn't, so hopefully its not the door motor.
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Burning Brakes
Joined: Jul 2002
Posts: 972
Likes: 0
From: Springdale AR
Re: Heater core HELP?!?!?!?! (SPEED750)
Hey speed750, I'm not trying to start on a different thread within this thread, but I just noticed you are from Navarre, Fl. I have been through there dozens of times. Nice area. I stayed in Destin for about 3 mo last year, but I traveled back and forth to Perdido Key just west of Pensacola. Anyway :seeya
Thread Starter
Instructor
Joined: Sep 2003
Posts: 118
Likes: 1
From: Plano TX
Re: Heater core HELP?!?!?!?! (vette92_1)
Good call Speed750. I was blockage. I just couldn't believe it because the coolant has always been so clean. However, that was the problem...lil' backflush solved it. Looked like something in my lil' girl's diaper coming out of there. Kudos to the forum and it's members for great diagnosis on this and many of my past projects...it's what keeps this place so great! I guess I just get a lil' itchy to turn a wrench on it every now and then...especially when it's for someting I haven't take apart yet. Thanks again to all and to the greatness of the forum!!!
:hurray: :hurray: :hurray:
:hurray: :hurray: :hurray:
Burning Brakes
Joined: Aug 2000
Posts: 1,052
Likes: 1
From: traveling nowhere fast, FL
Re: Heater core HELP?!?!?!?! (greggo's 94LT1)
no heat? check or replace your thermostat. My factory LT1 thermo got stuck halfway open and would never heat up the core enough for heat, even though the heat gauge looked fine. New factory thermo and I got lots o heat