Okay, I am having one heck of a time figuring this out. I have a 69 Camaro RS headlight setup. All hoses are fine, not cracked, and hooked up with no leaks anywhere. My canisters are working perfectly. I replaced my tank and my tank relay, thinking they were the problem, but that didn't work. The hoses under the dash at the headlight switch are attached with no leaks either.
When I use the override on the vacuum relay, the headlight doors open and close properly. When I pull the smaller hose off the relay, the doors open, and when I replace it, they close. If I use the override to open the doors, then turn on the headlights, and then put the override in the "normal" position and shut my headlights off, the doors close. What I can not do, is get the doors to open under normal circumstances (as in just turning on the headlight switch at the dash).
I have suction on the smaller vacuum relay hose when the lights are off, and no suction when I turn them on.
Any ideas? Suggestions? Thoughts? Further Questions?
How do I diagnose my dash switch to see if that is the problem? What line should have suction and when?
Any and all help is greatly appreciated.