wiper door
Burning Brakes
Joined: Jan 2009
Posts: 1,224
Likes: 1
From: Clarksville Indiana
I dont have much of a clue on the wipers or the lights, but there are some good threads in here for diagnosing vacuum problems. You need to see why you have vacuum to the diapham when you shouldnt. I think the line on the front closes the door and the line on the back side opens the door.
Team Owner
Joined: Jul 1999
Posts: 65,492
Likes: 230
From: Orange Park Florida
the vacuum relay control line, the small one feeding the diaphram, that is set so that the small line has vac on it to pull the door DOWN....closed....so if there is a failure in that/those controls you have the door OPEN, so the wipers work....
there is a vacuum switch on the pass side wiper....there is a electrical vac relay that kills vac to the line when activaed by the wiper switch....behind the speedo down lo.....and of course the main feed vac line to the entire system....
so just remember the key to the signal system is suck Closed....
same with the headlights....no vac to the realy diaphram..it's OPEN for everything....
there is a vacuum switch on the pass side wiper....there is a electrical vac relay that kills vac to the line when activaed by the wiper switch....behind the speedo down lo.....and of course the main feed vac line to the entire system....
so just remember the key to the signal system is suck Closed....
same with the headlights....no vac to the realy diaphram..it's OPEN for everything....
Burning Brakes
Joined: Oct 2006
Posts: 1,044
Likes: 0
From: Henrico VA
You have a leak. Listen for hissing right after you turn your engine off and even while it is running. Having a friend stand over your open hood will help. If you discover the leak, you will be all set. Nothing vacuum-related on mine used to work, now it all does. 
Le Mans Master
Joined: Feb 2008
Posts: 8,515
Likes: 255
From: Rochester New York
the vacuum relay control line, the small one feeding the diaphram, that is set so that the small line has vac on it to pull the door DOWN....closed....so if there is a failure in that/those controls you have the door OPEN, so the wipers work....
there is a vacuum switch on the pass side wiper....there is a electrical vac relay that kills vac to the line when activaed by the wiper switch....behind the speedo down lo.....and of course the main feed vac line to the entire system....
so just remember the key to the signal system is suck Closed....
same with the headlights....no vac to the realy diaphram..it's OPEN for everything....
there is a vacuum switch on the pass side wiper....there is a electrical vac relay that kills vac to the line when activaed by the wiper switch....behind the speedo down lo.....and of course the main feed vac line to the entire system....
so just remember the key to the signal system is suck Closed....
same with the headlights....no vac to the realy diaphram..it's OPEN for everything....
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