HVAC Problem......
Thread Starter
Burning Brakes
Joined: May 2005
Posts: 1,158
Likes: 46
From: RedSoxNation Cape Cod, MA
HVAC Problem......
Hello
I got a little problem with my HVAC in my 99 Coupe. I have the basic HVAC system (not the dual zone). I never really use my a/c or heat all summer but its starting to get colder around here so I went to use my heat and the fan blows and works on all settings but not much air is comeing from the vents and when I switch to the different modes (floor, vents, or defrost) nothing really seams to change. Any ideas??? I believe this system is vac operated so any help would be great.
Thanks in advance for the help.
Jimbo
I got a little problem with my HVAC in my 99 Coupe. I have the basic HVAC system (not the dual zone). I never really use my a/c or heat all summer but its starting to get colder around here so I went to use my heat and the fan blows and works on all settings but not much air is comeing from the vents and when I switch to the different modes (floor, vents, or defrost) nothing really seams to change. Any ideas??? I believe this system is vac operated so any help would be great.
Thanks in advance for the help.
Jimbo
Race Director
Joined: Apr 2001
Posts: 19,329
Likes: 15
From: Saint Augustine, FL
Mid-TN Events Coordinator
St. Jude Donor '03-'04-'05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15-'16
If you have a acid based battery, make sure it's not leaking. More than likely it's leaked acid on to your HVAC vacuum line (below the battery) and your PCM!
I'm willing to bet that's your problem.
I'm willing to bet that's your problem.
Thread Starter
Burning Brakes
Joined: May 2005
Posts: 1,158
Likes: 46
From: RedSoxNation Cape Cod, MA
Thanks for your reply,
I actually have the battery out right now to look to see if I can find any vac lines. The battery is not leaking and doesnt show any signs of it ever have leaked. Where is the vac line located? all I see around the battery is a bunch of wires up agains the fender. Is it under the battery tray?
thanks again
Jimbo
I actually have the battery out right now to look to see if I can find any vac lines. The battery is not leaking and doesnt show any signs of it ever have leaked. Where is the vac line located? all I see around the battery is a bunch of wires up agains the fender. Is it under the battery tray?
thanks again
Jimbo
Instructor
Joined: Jul 2006
Posts: 137
Likes: 1
From: Litchfield Park AZ
Originally Posted by jimbo1972
Thanks for your reply,
I actually have the battery out right now to look to see if I can find any vac lines. The battery is not leaking and doesnt show any signs of it ever have leaked. Where is the vac line located? all I see around the battery is a bunch of wires up agains the fender. Is it under the battery tray?
thanks again
Jimbo
I actually have the battery out right now to look to see if I can find any vac lines. The battery is not leaking and doesnt show any signs of it ever have leaked. Where is the vac line located? all I see around the battery is a bunch of wires up agains the fender. Is it under the battery tray?
thanks again
Jimbo
Race Director
Joined: Apr 2001
Posts: 19,329
Likes: 15
From: Saint Augustine, FL
Mid-TN Events Coordinator
St. Jude Donor '03-'04-'05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15-'16
Originally Posted by Bigfoot99
I had a similar problem, follow the link and you can see my fix. Click on AC repair.http://members.***.net/9vette9/
Mine was much worse. The problem is, the vacuum line can 'suck' acid up into itself, and then into the wiring harness. It can get real ugly if it's not caught in time. Luckily my only damage was the corregated plastic wrapped around the wiring harness, and the vacuum line.
Thread Starter
Burning Brakes
Joined: May 2005
Posts: 1,158
Likes: 46
From: RedSoxNation Cape Cod, MA
Thanks for the help, but my computer wont open up that power point presentation.
Does anyone else have a wright up or can expain to me what to do.
Thanks agian
Jimbo
Does anyone else have a wright up or can expain to me what to do.
Thanks agian
Jimbo
Burning Brakes
Joined: Sep 2006
Posts: 985
Likes: 0
From: Cumming Georgia
Thank you for the info
Hi,
I am still lurking on the forum, and eagerly waiting for my 2K Corvette, which I will get in November. Articles like this are very useful, and I am really looking forward to ownership. I do all my own work whenever possible, and realize the the Corvette is going to be more "high maintenance" than my little truck. With enthusiasts like you posting articles like this, I will be able to afford owning a Corvette, as well as enjoying one. Funny, I wasn't able to find any enthusiast forums for a Town Car. They are nice too, and also get kind of goofy in the electrical department : ).
Tim Glover
I am still lurking on the forum, and eagerly waiting for my 2K Corvette, which I will get in November. Articles like this are very useful, and I am really looking forward to ownership. I do all my own work whenever possible, and realize the the Corvette is going to be more "high maintenance" than my little truck. With enthusiasts like you posting articles like this, I will be able to afford owning a Corvette, as well as enjoying one. Funny, I wasn't able to find any enthusiast forums for a Town Car. They are nice too, and also get kind of goofy in the electrical department : ).
Tim Glover
Race Director
Joined: Apr 2001
Posts: 19,329
Likes: 15
From: Saint Augustine, FL
Mid-TN Events Coordinator
St. Jude Donor '03-'04-'05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15-'16
Originally Posted by jimbo1972
Thanks for the help, but my computer wont open up that power point presentation.
Does anyone else have a wright up or can expain to me what to do.
Thanks agian
Jimbo
Does anyone else have a wright up or can expain to me what to do.
Thanks agian
Jimbo
Remove your battery.
Remove the 4 bolts that hold down the battery tray.
Once you get the battery tray out, you should have pretty clear access to view you PCM, vacuum hose and wiring harness.
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Advanced
Joined: Jul 2006
Posts: 69
Likes: 0
From: Eagan MN
Originally Posted by jimbo1972
Thanks for the help, but my computer wont open up that power point presentation.
Does anyone else have a wright up or can expain to me what to do.
Thanks agian
Jimbo
Does anyone else have a wright up or can expain to me what to do.
Thanks agian
Jimbo
Here you go jimbo... A link with pics in it!
http://forums.corvetteforum.com/show....php?t=1422586
just fixed mine last night, works great now...
Thread Starter
Burning Brakes
Joined: May 2005
Posts: 1,158
Likes: 46
From: RedSoxNation Cape Cod, MA
Thanks for the help, I located the vac lines and the check valve but cant find the end of one of the vac lines to reconnect it.
There is a vac line comeing from the pass side inside of the car going to the check valve.
There is a line from the check valve to the black box its connected to.
But where does the vac line go from the check valve to the engine??
Its broken off about 6" from the check valve and i cant find the other end? any ideas??
thanks
Jimbo
There is a vac line comeing from the pass side inside of the car going to the check valve.
There is a line from the check valve to the black box its connected to.
But where does the vac line go from the check valve to the engine??
Its broken off about 6" from the check valve and i cant find the other end? any ideas??
thanks
Jimbo
Instructor
Joined: Jul 2006
Posts: 137
Likes: 1
From: Litchfield Park AZ
Originally Posted by jimbo1972
Thanks for the help, I located the vac lines and the check valve but cant find the end of one of the vac lines to reconnect it.
There is a vac line comeing from the pass side inside of the car going to the check valve.
There is a line from the check valve to the black box its connected to.
But where does the vac line go from the check valve to the engine??
Its broken off about 6" from the check valve and i cant find the other end? any ideas??
thanks
Jimbo
There is a vac line comeing from the pass side inside of the car going to the check valve.
There is a line from the check valve to the black box its connected to.
But where does the vac line go from the check valve to the engine??
Its broken off about 6" from the check valve and i cant find the other end? any ideas??
thanks
Jimbo
Thread Starter
Burning Brakes
Joined: May 2005
Posts: 1,158
Likes: 46
From: RedSoxNation Cape Cod, MA
I found it! Its located in the big wire loom that goes along the firewall, I cut it open and found it in there, it was hideing from me. Its the vac line that goes all the way back to the intake manifold. Looks like it just got brittle and broke because I have no signs of a battery leak.
Thanks everyone for your input and help, I really appriciate it
Jimbo
Thanks everyone for your input and help, I really appriciate it
Jimbo
Racer
Joined: Jan 2006
Posts: 479
Likes: 2
From: Hollywood Maryland
A little extra protection
I wound up doing this repair twice thanks to a second leaking battery. When I fixed the vacum lines the second time, I cut back the supply line (from the MAP sensor on the intake manifold) just inside the battery compartment and spliced in a new line. I also spliced in a new line HVAC line to the firewall. Put in a new vacum check valve. I encased the vacum lines in rubberized 1/4" fuel line by cutting the new vacum lines to length and then making a sheath with the fuel line. Now nothing can get to those vacum lines again. The fuel line hose can be bought at any home improvement store and is impervious to grease, oil, water, and battery acid. I bought 3' for repairs in the battery compartment area and it was plenty. Good luck.
Instructor
Joined: Jul 2006
Posts: 137
Likes: 1
From: Litchfield Park AZ
Originally Posted by jimbo1972
I found it! Its located in the big wire loom that goes along the firewall, I cut it open and found it in there, it was hideing from me. Its the vac line that goes all the way back to the intake manifold. Looks like it just got brittle and broke because I have no signs of a battery leak.
Thanks everyone for your input and help, I really appriciate it
Jimbo
Thanks everyone for your input and help, I really appriciate it
Jimbo