Home page
SPONSOR AD

Support our Vendors!  |  Advertise Here

Topic: Center Vent AC

in Forum: C4 Cooling and Heating Systems


Already a Member?
Login
Not yet a Member?
Register for Free!

Center Vent AC (1/5)
 5/11/10 1:50pm
bagpipedave
Standard Member
Send Private Message

Orange Park, FL - USA

Vette(s):
1996 LT4 Blk/Blk coupe all origional


Joined: 12/4/2009
Posts: 56

I've had my '96 LT4 for just over a year and have read everything I could find on the car. Somewhere in my reading I remember a statement that indicated if no AC was coming out of the dash vents it was an indication something expensive was about to give up. I can't find the refference again and I'm not getting any output from my dash vent on heat or AC. I have the electronic climate control and it does heat and cool the car and I'm picking up no faults on the OBD II diognostics. Can anyone help me remember what unit was failing that would cause this condition. Everything else..blower,temp select, fan select all seem to be working fine.
Dave
Our Sponsors help support C4VR
Center Vent AC (2/5)
 5/11/10 8:45pm
96LT1
Former Member

Send Private Message

Powhatan, VA - USA

Vette(s):
1996 Polo Green LT1 Coupe


Joined: 3/20/2009
Posts: 305

I'm GUESSING you may be talking about the programmer ?? I've got to ask though--when you push defrost or the floor vent buttons--do they still work correctly?
 
                                                                                                      Vaughn
Center Vent AC (3/5)
 5/11/10 10:02pm
bagpipedave
Standard Member
Send Private Message

Orange Park, FL - USA

Vette(s):
1996 LT4 Blk/Blk coupe all origional


Joined: 12/4/2009
Posts: 56

Vaughn, I went out and tried it today (61degF) and the defrost and floor vents work seperately and together. With the car fully warmed up and pushed the button for floor and dash about 90% of the heat came from the floor and I was still getting heat from the defrost. A very SLIGHT flow of heat came from the dash vents with the temp set on 82 and fan on 8. The floor and defrost vents flow with any buttons pushed. I have tried the same process when the temp outside was in the 90's with same results. Programmer sounds familiar..can you tell me more about it. I have the factory shop manuals, Chilton, Haynes and numerous magazine articles to ref. I just did the Optispark and waterpump last month and the car runs about 20deg cooler now. When I took off the injector cover on the left side a vacume device was broken loose and I replaced it. Two hoses came into the device and an elbow went into the intake. Thanks for your time and consideration.  Dave
Center Vent AC (4/5)
 5/12/10 5:59am
96LT1
Former Member

Send Private Message

Powhatan, VA - USA

Vette(s):
1996 Polo Green LT1 Coupe


Joined: 3/20/2009
Posts: 305

The programmer is behind the inst. and to the right towards the center of the dash--vacuum ports (inside the programmer)which are controlled electrically via the control head---allow vacuum to flow to servos which control doors-that when open allow air flow to defrost--floor or dash vents depending on the button which is pushed.
 
The "source" vacuum for the programmer is the cruise vacuum fitting under the fuel rail (sounds like what you've already replaced)----if you're SURE all is good in that area---then next IMO would be to check the programmer and the vacuum "harness" which goes to it. The vacuum nipples on the programmer are known to crack or distort (over time/age) and allow a vacuum leak so that the different modes don't work correctly. The vacuum harness itself has very small hoses (almost looks like a wiring harness)--which once again overtime and w/age can become kinked or collapsed.  Smile Hope this helps.
 
                                                                                                      Vaughn
Center Vent AC (5/5)
 5/12/10 12:44pm
bagpipedave
Standard Member
Send Private Message

Orange Park, FL - USA

Vette(s):
1996 LT4 Blk/Blk coupe all origional


Joined: 12/4/2009
Posts: 56

Thanks Vaughn, I'll continue to check it out.
Our Sponsors help support C4VR