Corvette1$

1978 Silver Anniversary / L-82

the other day i had my headlights up and when i went to put them down the lights went off, but they stayed up. I have been all over the car and don't think there is a vacume leak. i manually put the lights down, they stayed down, but when i started the car, they both went right back up. When the car is running there is too much pressure to force them down manually, so I think the vacume system is working right.

Is there a relay or something that is causing them to remain up?

1979toy

Welcome to the forum! Always glad to have a new member.
The is a switch at the bottom of the dash, below the steering column, that raises the headlights to wash or replace them. If the switch is pulled out the headlights will go up and stay up. Check that.
If that isn't your problem, there is a one way valve located in the vacuum line in the area of left of the distributor. It is a three way valve that runs from the manifold to the switch under the dash and the headlight reservoir. That valve can go bad.
Good luck with it.

jerryp58

Did this "just" happen? If so, that's a relatively good thing (it shouldn't be leaking actuators or actuator seals), and it's hopefully good that it happened to both headlights (should narrow down the search for problem areas).

Mine did the same thing one day and it turned out to be the headlight switch.

I'm assuming that the headlight switch on your '78 is the same as my '77. If so, the vacuum runs through there too. My switch developed a vacuum leak and both lights would stay up. The switch is a fairly easy change on a '77 because you can loosen all of the dash screws, remove the two bolts holding the steering column in place (and let the column drop a couple of inches) and then you can pull the dash forward enough to get at the switch (if that's the problem).

Oh, and Welcome :seeya


[Modified by jerryp58, 9:07 PM 11/11/2001]

Corvette1$

thanks so much 1979toy, it worked. :)
:cheers: