Air Blowwing Out Wrong Vents- Chevy Lumina

Question:
1997 Chevy Lumina, 3.1L. I have this weird problem with my vent system. You know how there are 3 different vents positions (floor, the ones on the instrument panel, and the one under the windshield) but lately I can't switch to the ones on the instrument panel and the other two don't come off. Also my A/C is very weak and I think it doesn't work properly. I am sure that the switches them self work just fine, I think it's some thing else.

Answer:
Sounds like definitely a vacuum problem. The mode switch on the control head controls the vacuum/electric solenoid block, which in turn directs vacuum to the proper mode or blend doors. When there is a loss of main vacuum to the solenoid, the system defaults to def/flor for safety reasons. First need to check for vacuum at the purple and the black hoses on the solenoid assembly with the engine running.

That is under passenger side dash, above the blower motor. If no vacuum there then check vacuum into the vacuum ball. The engine supplies vacuum to it. The vacuum ball is under the driver side inner wheel well shield. One hose should have vacuum in, the other goes to the solenoid assembly. If there is vacuum at the solenoid, then a possible control head switch problem.


 

Question:
1997 Chevy Lumina, 3.1 Liter. A while back ago i wrote about a broken vacuum ball in my Chevy Lumina. I fixed it and it works fine ever since. Now in the FREAKING HOT SUMMER! It's kinda cool but not cool enough for me. How do I check the freon level? Refill it? And drain the old stuff?

Answer:
Happy to hear about the vacuum thing. The a/c ports are real tough to get to. Unsecure the air cleaner box. Would suggest having a mechanic check your freon charge and add if need. The system deals with very high pressures. You can get a can of freon at a parts store with a hose and fitting and follow direction CAREFULLY if you so wish.

Visitor Reply:
Ok, I'll just have somebody check it. I notice that a lot, that the Lumina has a lot of stuff in the wrong places. Seems to me that it's kind of messed up. Like the battery is under the windshield fluid reservoir and when I changed my air filter it's in a box that you had to unscrew and it got really messy when there was a power cable running over it and I hand to pull the old one out and the stuff the new one it... OK well thanks for the help.

Answer:
Wow. Sounds like someone that does not know what they are doing has messed things up under the hood. That could mean your car has more problems with the vents and A/C than you think.


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