flynhi

Doing final checks before buttoning up the dash on my 71 and I have a vacuum problem.
After start when vacuum comes up, both wiper door and headlights come up. Each will go down when its respective override switch is opened.
What's up with this?

87bob

I think you may have a hoses reversed that is why the come up.

wayne_69_427

I think 87bob is on the right track

vettfixr

:iagree:

flynhi

87bob,
Any idea which hoses could be switched that woould affect both systems?

flynhi

ttt

jerryjfunk

Which port do you run your headlights off of?

flynhi

Primary vacuum is off the plenum of the TPI. Then to the vacuum reservoir under the driver side fender.
All plumbing forward of the res is as per AIM. I'm tracing plumbing on drivers side of firewall. Connections at the check valve on the back of the tach are suspect.
Any ideas on what could be wrong in this area that would cause my problem?

Fleetwood

you may have a fault in one of the components,check out this web site & do a few tests. http://www.corvette-101.com