Weak A/C blower. 89
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2025 C7 of the Year Finalist- Unmodified
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Weak A/C blower. 89
It seems like my A/C blower doesnt have much push for air flow. I have had the bolwer motor out and didnt see any debre. Its the original blower motor. Any sugestions? The rest of the A/C system is working correctly. Do these motor's gradually die? Any way to test the motor?
Thanks for all input.
Corvette Mike
Thanks for all input.
Corvette Mike
Le Mans Master
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From: Australia
Have you tried running 12V direct from the battery to the blower motor to see if it spins faster than what you have now?
Problem may be with the blower control module (C68 Elec A/c ) that controls fan speed or with the man A/c resistors are switched to change speed
Problem may be with the blower control module (C68 Elec A/c ) that controls fan speed or with the man A/c resistors are switched to change speed
Last edited by rodj; Jun 27, 2009 at 12:29 AM.
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St. Jude Donor '10-'11
I have pondered this quiestion myself many times. The heat in my car will burn your feet. The AC hardly comes out of the vents. Maybe it's just a defect in the C4s? I have never been able to get my AC strong likem y other cars. The only vents that have any air come out of them are the middle ones. Hardly any comes out of the drivers or passengers vent. Thats with a new motor as well.
It's cold now. Just doesn't blow hard enough.
It's cold now. Just doesn't blow hard enough.
Le Mans Master
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From: San Diego, Ca
Always start by jumpering the motor directly to the battery - examine the connector for discoloration which would indicate a voltage drop. Terminals are crimped to the leads so taking apart the Weatherpak and adding some solder is sometimes necessary.
Check around the Evaporator Case - especially at the bottom - for leaks. If the Evaporator has been replaced it may not have been sealed up correctly.
Duct work is sealed with foam and it's probably shot after 20 or so years. Remove the passenger side hush panel - if there's a flow of air towards your feet, the duct work is leaking. Pull the dash cover and seal the joints with duct tape or anything you can find at Home Depot.
Check around the Evaporator Case - especially at the bottom - for leaks. If the Evaporator has been replaced it may not have been sealed up correctly.
Duct work is sealed with foam and it's probably shot after 20 or so years. Remove the passenger side hush panel - if there's a flow of air towards your feet, the duct work is leaking. Pull the dash cover and seal the joints with duct tape or anything you can find at Home Depot.
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St. Jude Donor '10-'11
Always start by jumpering the motor directly to the battery - examine the connector for discoloration which would indicate a voltage drop. Terminals are crimped to the leads so taking apart the Weatherpak and adding some solder is sometimes necessary.
Check around the Evaporator Case - especially at the bottom - for leaks. If the Evaporator has been replaced it may not have been sealed up correctly.
Duct work is sealed with foam and it's probably shot after 20 or so years. Remove the passenger side hush panel - if there's a flow of air towards your feet, the duct work is leaking. Pull the dash cover and seal the joints with duct tape or anything you can find at Home Depot.
Check around the Evaporator Case - especially at the bottom - for leaks. If the Evaporator has been replaced it may not have been sealed up correctly.
Duct work is sealed with foam and it's probably shot after 20 or so years. Remove the passenger side hush panel - if there's a flow of air towards your feet, the duct work is leaking. Pull the dash cover and seal the joints with duct tape or anything you can find at Home Depot.
I did that. My AC vent did not fit snugly. I used duct tape and a steel clamp. Air tight now.
The air that comes out is ice cold now. It's just it hardly comes out. I installed a new fan and motor. Made sure all the vents are tight. Hmm...
Le Mans Master
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From: Tampa Florida
check the evaporator case seals first. Debris could also be blocking the coil evaporator coils also as well....which can be very difficult to see unless the covers are pulled. Here is a pic of an '89 without the outer covers on the system.
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My previous "89" Vette had the same weak blower problem.
I had an AC shop check the AC system and everything was fine except the previous owner did the 134A retrofit which didn't blow as cold as R12.
I checked the evaporator for debris and replaced the blower motor just for the heck of it and it still didn't provide anymore air flow.
The "89" Vette was totaled a year later and I bought a "91" which has a lot more air flow from the blower.
Since you're the original owner, has the air speed from the blower always been weak or, is this something that you've just noticed?
I had an AC shop check the AC system and everything was fine except the previous owner did the 134A retrofit which didn't blow as cold as R12.
I checked the evaporator for debris and replaced the blower motor just for the heck of it and it still didn't provide anymore air flow.
The "89" Vette was totaled a year later and I bought a "91" which has a lot more air flow from the blower.
Since you're the original owner, has the air speed from the blower always been weak or, is this something that you've just noticed?
Last edited by GKK; Jun 28, 2009 at 10:52 AM.
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From: The opposite of there.
My '89 had the same problem. It was blowing weakly at top and weakly at the bottom. I fixed it by going under the dash on the drivers side and checking the vacuum manifold. Mine had an extra "port" on it that was open. I plugged the port and this made all the inner doors in the system close and open properly. Now you can sit in the drivers seat and feel the breeze on your face.
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blower
Seems like it has always been weak. I remember when I got it how weak it was to my other cars.
Mike
Mike
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What did you use to seal that up? I noticed on my 89, where the two metal lines go into the box. There is some black puddy there. But the puddy isn't really sealing anything as I can feel air blowing out it.
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My '89 had the same problem. It was blowing weakly at top and weakly at the bottom. I fixed it by going under the dash on the drivers side and checking the vacuum manifold. Mine had an extra "port" on it that was open. I plugged the port and this made all the inner doors in the system close and open properly. Now you can sit in the drivers seat and feel the breeze on your face.
Is it on the programmer?
