Bad Headlight Actuator
Thread Starter
Melting Slicks
Joined: May 2006
Posts: 2,369
Likes: 103
From: Centerville Louisiana
Bad Headlight Actuator
Those of you with leaking actuators. Do you notice a engine miss because of the vacuum leak? I'm trying to track down a leak that goes away when I isolate the headlight system. I've changed the hoses checked relays only issue is a leak on the red hose side of one. With all the lazy, slow working system seems like engine performance would suffer enough to fix it right away
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
Your leak is likely in the vacuum relays feeding the actuators. But, I doubt that you are getting a spark miss from that. Just block off all the vacuum lines from carb and intake manifold...except for the distributor vacuum advance...then see if you still have a spark miss. My guess is that you will; and that should prove that the vacuum system is not the cause.
Last edited by 7T1vette; Jul 9, 2016 at 12:26 AM.
Thread Starter
Melting Slicks
Joined: May 2006
Posts: 2,369
Likes: 103
From: Centerville Louisiana
I isolated the line right after the check valve and miss goes away. When I plug it back in to cycle the lights it's back. I bought hose kit and new check valve after checking relays using Willcox instruction they appear to be good. The driver side actuator won't hold vacuum on the red hose side steady drops off after pumping to 15". Of course that side requires new can.
Race Director
Joined: Apr 2007
Posts: 11,152
Likes: 890
From: South Western Ontario
When I was helping the old man with his car the leaking actuator has no noticeable effect on the engine vacuum. So, there is a restriction in the line to the tank somewhere in the system.
Drifting
Joined: Jul 2006
Posts: 1,259
Likes: 154
From: Deplorableville Nebraska
Without testing every component in your vacuum system, it's really difficult to surmise exactly which component is at fault. If you suspect a particular component, try pinching the vacuum line going to the component and do your test.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
Either that headlamp vacuum relay is really leaking a bunch, or your car is way lean on the idle to begin with. I believe your results; it's just that there can't be all that much extra air coming in through that relay valve. That's why I think your idle mixture may be on the "lean" side.
In any event, you've tested it and you got clear results. Find whatever in that vacuum line/series that is leaking (it could be MORE than just that relay), repair/replace it, and hopefully that will solve your problem.
In any event, you've tested it and you got clear results. Find whatever in that vacuum line/series that is leaking (it could be MORE than just that relay), repair/replace it, and hopefully that will solve your problem.
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