Frustrated!
Le Mans Master
Joined: Aug 2006
Posts: 7,426
Likes: 1,559
From: mount holly NC
2025 c3 ('74-'82) of the Year Finalist - Unmodified
2019 C3 of Year Finalist (appearance mods)
Start at the manifold and follow the diagram and make sure that you connected everything correctly.
http://www.corvette-101.com/vacuum.htm
http://www.corvette-101.com/vacuum.htm
Burning Brakes
Joined: Mar 2016
Posts: 1,008
Likes: 163
Do you have a hand vacuum pump? If not, rent one from your local auto parts store for free. Then you can hook it up to the headlight actuators and pump them by hand and you should see them slowly rise. That way you can at least verify that they are working properly, which would narrow your leak down.
You can also use that hand pump to verify each vacuum hose and relay to make sure they aren't leaking.
You can also use that hand pump to verify each vacuum hose and relay to make sure they aren't leaking.
Thread Starter
Cruising
Joined: Apr 2016
Posts: 11
Likes: 0
I changed all the vacuum hoses and rebuilt the actuators, which I thought that was the problem because they were pretty bad, but no, the car was parked in a barn for acouple years, when I took started taking the interior out I found several rat nest in the car, One particularly inside the dash on top of the light switch, so my next step was to buy a new switch.
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,754
From: Charlotte NC
That may not be your problem. Just saying....there is way to verify if it is good or not. Also assuming that you replaced the vacuum hoses that go to your headlight switch or at least test them to make sure some rat did not eat a hole in one of them.
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Verdad Gallardo
Safety Car
Joined: Nov 2008
Posts: 3,717
Likes: 551
From: Seattle Washington
Sounds like You are starting to guess and replace parts. Almost always the problem is a Vacuum leak. You can hear a Vacuum leak if you eliminate the noise of the Engine. To do this run a long hose out of your garage to another car and or to a Vacuum pump. A sucking sound will lead you to the problem and or problems. No leak ? Ok now start at the engine and disconnect the first hose and stick a Vacuum gauge in it. There is probably 12-15 ins of Vacuum. Now go to the next hose and do the same thing, and on down the line till You find something that is blocking the flow.
Thread Starter
Cruising
Joined: Apr 2016
Posts: 11
Likes: 0
Sounds like You are starting to guess and replace parts. Almost always the problem is a Vacuum leak. You can hear a Vacuum leak if you eliminate the noise of the Engine. To do this run a long hose out of your garage to another car and or to a Vacuum pump. A sucking sound will lead you to the problem and or problems. No leak ? Ok now start at the engine and disconnect the first hose and stick a Vacuum gauge in it. There is probably 12-15 ins of Vacuum. Now go to the next hose and do the same thing, and on down the line till You find something that is blocking the flow.