Ventilation fan problem....need diagnosis.
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Le Mans Master
Joined: Jul 2000
Posts: 7,638
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From: Greenville SC
Ventilation fan problem....need diagnosis.
My vent fan will not come on sometimes when I start the car. If I go over a sharp bump/hole it will turn on. Is this just a loose connection or is it the HVAC controller?
If it is the controller where can I find a good deal on one? Jeff Koope?
If it is the controller where can I find a good deal on one? Jeff Koope?
Le Mans Master
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From: Life is just one big track event. Everything before and after is prep and warm-up and cool-down laps
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St. Jude Donor '12
Re: Ventilation fan problem....need diagnosis. (95wht6spd)
Stert with the easy cheap stuff before you spend a ton of money on it throwing parts at it.
Find the connection where the wires plug into the blower motor. Make sure its well plugged in. Jiggle the connector when the AC is on and see if that cuts the blower on. If this works then replace the blower motor and you are done. This is the problem that I had on my 88.
If not follow the wires and check each connection under the hood.
If that doesn't work then take apart the center and clean the contacts between the wires and the controller.
Find the connection where the wires plug into the blower motor. Make sure its well plugged in. Jiggle the connector when the AC is on and see if that cuts the blower on. If this works then replace the blower motor and you are done. This is the problem that I had on my 88.
If not follow the wires and check each connection under the hood.
If that doesn't work then take apart the center and clean the contacts between the wires and the controller.
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Joined: May 2001
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From: Yokosuka
Re: Ventilation fan problem....need diagnosis. (jaa1988)
Another thought... Tap on the fan housing to see if it will come on. Had a blower that would not operate for me once but would operate once I hit a bump. Tapped the fan housing and like magic it was on. This maybe the easy way to tell if you need to replace the blower.
:smash:
:smash:
Thread Starter
Le Mans Master
Joined: Jul 2000
Posts: 7,638
Likes: 326
From: Greenville SC
Re: Ventilation fan problem....need diagnosis. (jaa1988)
OK, but where is the blower? Under the dash or in the engine bay? Is it easy to get to or or do I have to disassemble a lot of things?
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From: Life is just one big track event. Everything before and after is prep and warm-up and cool-down laps
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St. Jude Donor '12
Re: Ventilation fan problem....need diagnosis. (95wht6spd)
Don't know if they moved it but mine is acessible with the hood open. Its on the passenger side up against the firewall. I had to loosen up the plastic around the wheel to wiggile it in and out.
:cheers: :cheers: :cheers:
:cheers: :cheers: :cheers:
Thread Starter
Le Mans Master
Joined: Jul 2000
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From: Greenville SC
Re: Ventilation fan problem....need diagnosis. (jaa1988)
What does it look like? Is it around the coolant fill cap area or underneath? What does the wire look like that I need to check and what is it buy? Does it have wire loom or anything on it?
Le Mans Master
Joined: Mar 2001
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From: Life is just one big track event. Everything before and after is prep and warm-up and cool-down laps
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St. Jude Donor '12
Re: Ventilation fan problem....need diagnosis. (95wht6spd)
What does it look like? Is it around the coolant fill cap area or underneath? What does the wire look like that I need to check and what is it buy? Does it have wire loom or anything on it?
Go to the passenger side
look in the space next to where all the ac lines run into the firewall
towards the bodywork you should see a round metal casing.
There should be a wire plugged into it (on my 88 it was on the side near the engine)
If jiggling the wire while your fan should be running causes the fan to run call your favorite auto parts place and ask them for a blower motor for your year. Mine was about $50 without the "squirrel cage". You should be able to swap it from one fan to the other. Mine was held on by one nut.
Good luck!
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Thread Starter
Le Mans Master
Joined: Jul 2000
Posts: 7,638
Likes: 326
From: Greenville SC
Re: Ventilation fan problem....need diagnosis. (jaa1988)
OK I checked it out. I didn't think that was the blower, because it had a sticker on it specifying the type of refrigerant to use.
Anyway, the blower works, but I just realized the problem is that the air is only coming out of the defrost vents! Will not change with any selection. Do I need a new AC controller? I never noticed this while driving because it is to loud and didn't notice the blower was still on, but just not blowing in the correvt vents.
Anyway, the blower works, but I just realized the problem is that the air is only coming out of the defrost vents! Will not change with any selection. Do I need a new AC controller? I never noticed this while driving because it is to loud and didn't notice the blower was still on, but just not blowing in the correvt vents.
Le Mans Master
Joined: Mar 2001
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From: Life is just one big track event. Everything before and after is prep and warm-up and cool-down laps
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St. Jude Donor '12
Re: Ventilation fan problem....need diagnosis. (95wht6spd)
OK I checked it out. I didn't think that was the blower, because it had a sticker on it specifying the type of refrigerant to use.
Anyway, the blower works, but I just realized the problem is that the air is only coming out of the defrost vents! Will not change with any selection. Do I need a new AC controller? I never noticed this while driving because it is to loud and didn't notice the blower was still on, but just not blowing in the correvt vents.
Anyway, the blower works, but I just realized the problem is that the air is only coming out of the defrost vents! Will not change with any selection. Do I need a new AC controller? I never noticed this while driving because it is to loud and didn't notice the blower was still on, but just not blowing in the correvt vents.
Check all the vaccum lines
Since yours is completely setup differently than mine you'll want to find someone that has a service manual and can point you to where all the connections are.
Good Luck
Thread Starter
Le Mans Master
Joined: Jul 2000
Posts: 7,638
Likes: 326
From: Greenville SC
Re: Ventilation fan problem....need diagnosis. (jaa1988)
I checked the T fitting under the passenger side fuel rail and it is OK. Where are the other vacuum lines? I looked under the dash over the gas pedal for the controller, but didn't see a controller.
Thread Starter
Le Mans Master
Joined: Jul 2000
Posts: 7,638
Likes: 326
From: Greenville SC
Re: Ventilation fan problem....need diagnosis. (95wht6spd)
There is a small rectangular plastic box with several hoses going into it under the fuel rail cover near the throtle body. One of the hoses leads down to around the blower. Are these vacumm lines? The are bigger than the lines on the T fitting and have small ribs on the onw going to around the blower.
