1988 Corvette Auto Vacuum lines
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1988 Corvette Auto Vacuum lines
Due to a little fire (shakes head) I melted a bunch of my vacuum lines that feed my Fuel pump regulator, EGr valve and I assume HVAC Lines, a vacuume line that goes under the plenum throttle body on the drivers side. Can anyone send pictures of their vacuume line set ups so I can repair my idiotic mistake. Here are the pictures I have. Thanks again.
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The rear port connects to plastic hardline out of the firewall harness for the HVAC controls inside.
The rubber hose on the side port goes to the vac ball under the drv side headlight (with a T off to the CC)
Front port of valve goes to the port on plenum shown in diagram marked HVAC
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Thank you for the response.....I have seen this picture...but it does not seem apply to the `88 corvette. I see where the egr valve connects to that drivers side port. But that picture I sent where it has the two lines going to one when I followed it enters a ball on the driver side fender.That means the two ports on the intake are still open after Ive connected the egr valve. What I don't understand is how the fuel pump regulator and those two open lines get connected.
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Is your vac plumbing stock?
Do you have all the factory emissions stuff and plumbing in place?
If not ,your vac system has been modified so the stock diagram does out the window
All you need is a hose from one of the plenum ports direct to the fuel reg and one to the one way valve shown
there is no reason for the EGR vac to be connected to the vac ball
Do you have all the factory emissions stuff and plumbing in place?
If not ,your vac system has been modified so the stock diagram does out the window
there is no reason for the EGR vac to be connected to the vac ball
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The EGR valve is not connected to the VAC ball. The EGR is going to get connected to picture #3. The Fuel pressure regulator will get attached to one of the Intake ports. Picture # 2 will be attached to the other intake port. I think the hvac connection to the fire wall is melted as I don't see it.
Last edited by Supahone; Oct 20, 2013 at 11:05 PM.
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Thank you for your help. I had to peel back the HVAC harness to find the plastic line and reconnected the hvac to the intake manifold. And the Fuel pump regulator to the intake line. I will get fresh vacuum lines to reattach the erg. Thank you all for your help will keep you updated.
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From: Anaheim CA
You setup may be different (they kept changing things over the years), but on my car the front vacuum port goes into a vacuum "harness" (as GM calls it) that connects to the A.I.R. solenoids on the front of the engine and the fuel pressure regulator. It's part number 14082463. I paid around $12 for this one a few years ago.
You're lucky to be able to attach to the HVAC vacuum line going into the cabin. When I had my fire it was melted right down to nothing at the harness bulkhead feedthrough. I had to dig through a lot of sticky yellow gunk to get to it and pull it out.
You're lucky to be able to attach to the HVAC vacuum line going into the cabin. When I had my fire it was melted right down to nothing at the harness bulkhead feedthrough. I had to dig through a lot of sticky yellow gunk to get to it and pull it out.
Last edited by Cliff Harris; Oct 21, 2013 at 03:08 AM.
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Been doing allot of reading on past threads...if i have spark....and fuel pressure....seems the lines hold allot of fuel.so that bad fUel is still in play. Will check for codes again...maybe it's my module...Will check my plugs as well.
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From: moraga ca
Cranking fuel parameters are preset by the ecu and only varies according to coolant temperature. The vacuum signal is zero until the car starts. The fuel pressure is ten decreased when the regulator sees idle vacuum.