i need some info on my climate control it onlly blow in the defrost and floor it will not change what should i be looking for?

 

Either a vacumn leak at the engine or the AC Controller is defective/ Chect the vacumn connection under the right fuel rail cover first.

 

thanks i will do that

 

do the appropriate lights go on when you push the various buttons to change from heat to defrost etc. On my 94 the controls would not work most of the time. The lights would not light nor would it function. I just took it apart and cleaned the contacts behind the buttons and now they work great.

 

Try looking here http://www.batee.com/corvette/acrepa...oard/c68.shtml

that is everything you need to know about the system.

 

It's for the 1984-1989 C4's. http://www.batee.com/corvette/acrepair/

 

yes i believe all the lights work but it want change its stuck on def. and floor

 

I had same problem,take off the right fuel rail cover there you will see a three way valve. It is probably broken off at the end,you can hear it blowing with the engine running. Put it back in, tape it or something and you will see. I was told it is called a divertor valve,one way valve, blender check valve , vacum delay valve. I don't know. The guys and gals here say autozone has it,I had to go to the dealer. 4.50 part.. Hope this is what it is....

 

okay i pulled the cover off and checked for vaccum leak but didnt see any i will recheck that 3 way valve i hope thats it this is the only thing i can find wrong i have only had her for about 5 weeks besides she needs two rear tires....

 

Actually it's a check valve allowing vacuum to only flow toward the control panel, or for electronic air, the Programmer. This, along with the storage tank, helps to maintain a constant, steady source of vacuum so that the a/c/heater/defrost doors remain open/closed (depending on the control panel settings) and don't fluctuate under borderline conditions. Vacuum that isn't being used could degrade engine performance, so it's always applied to the defroster doors, sucking them closed, even with heater/a/c off. When defrost is requested, the source is redirected closing the heater/a/c vent doors so, if there's only defrost, it isn't getting any vacuum. It's generally the check valve that's been mentioned and it can be checked by trying to blow air through it opposite the direction of flow - no air should pass. You can also disconnect it, making sure there's vacuum on the output side. The vacuum tank lines should be inspected for cracks too and it should hold at least 10 ins. of vacuum if you pump it up. If all this checks out, then you need to remove the Programmer and verify that vacuum is getting to it on the source line - black, and from there, output to the defroster door solenoid line - tan or red or both (depending on year), but you rarely need to get this far as it's usually the engine source or the check valve.

 

this check valve is the same three way valve that was mentioned?

 

Same problem here- it only blows hot; I saw the check valve, has 3 lines, bef valve and 2 after: one goes to contoller, other tees off to vacuum ball and cruise control from what I recal.. I'll check it tommorow..

 

mine will blow cold or hot but want move from def and floor its kind a aggervating trying to get the temp right so the window want fog...

 

The factory service manual has excellent trouble-shooting charts for tracking down problems in the AC. I started to make a copy and offer it up, but, unfortunately, a copy of that section would not only be illegal, but would in itself be a small book. I suggest you go to the Helms website and order the manual. It'll be the best money you'll ever spend on your baby.

 

yes there is like thre valves on that side one closest to firwall then theres another one and one more after that i dont here any kind of a vacuum leak unless one of those valves is stopped up but she dont lack in any power ??