Vacuum supply for HVAC
Thread Starter
Pro
Joined: Aug 2005
Posts: 503
Likes: 50
From: Bradenton, FL
Vacuum supply for HVAC
I've read the posts about fixing the vacuum leaks to get the HVAC from blowing our of all vents... I can find the vacuum canister behind the passenger side front quarter panel. What I can't find/see is the supply from the back of the engine. I can't even get my hand to the back of the engine to feel for it.
What am I missing?
What am I missing?
Drifting
Joined: Sep 2009
Posts: 1,862
Likes: 594
From: Prescott, Arizona
It comes off the rear of the intake manifold and enters a wire loom with various wires to go down to below the battery. Black plastic tube less than 1/4" OD. Check this thread:
https://www.corvetteforum.com/forums...with-pics.html
https://www.corvetteforum.com/forums...with-pics.html
Thread Starter
Pro
Joined: Aug 2005
Posts: 503
Likes: 50
From: Bradenton, FL
It comes off the rear of the intake manifold and enters a wire loom with various wires to go down to below the battery. Black plastic tube less than 1/4" OD. Check this thread:
https://www.corvetteforum.com/forums...with-pics.html
https://www.corvetteforum.com/forums...with-pics.html
I am familiar (by way of posts and pics) on where is originates off the back of the intake manifold. My problem is I just can't see it or feel it or even get my hand to the back of the manifold. . Wondering if there is some sort of trick that I am missing other than pull the intake manifold...
Drifting
Joined: Sep 2009
Posts: 1,862
Likes: 594
From: Prescott, Arizona
I don't know of any way to get to it there other than to remove the manifold. I've had mine off twice, once for the oil pressure sender, the second to relocate the oil pressure sender, add insulation under the manifold and to add rear coolant air bleed lines. A good time to do everything back there including extending the vacuum tube enough to make re installation of the manifold easier.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
You really need to remove the intake. Be prepared to extend the vacuum line to make it easier to work with. That short line that the factory provided sucks!
The line is nylon and can crack/rot and leak. If that's the case, be prepared to run all new line.
You can test the vacuum supply line to the canister with the engine running. Should have VACUUM at that line if its properly connected to the manifold and not damaged..
Bill
The line is nylon and can crack/rot and leak. If that's the case, be prepared to run all new line.
You can test the vacuum supply line to the canister with the engine running. Should have VACUUM at that line if its properly connected to the manifold and not damaged..
Bill
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
You really need to remove the intake. Be prepared to extend the vacuum line to make it easier to work with. That short line that the factory provided sucks!
The line is nylon and can crack/rot and leak. If that's the case, be prepared to run all new line.
You can test the vacuum supply line to the canister with the engine running. Should have VACUUM at that line if its properly connected to the manifold and not damaged..
Bill
The line is nylon and can crack/rot and leak. If that's the case, be prepared to run all new line.
You can test the vacuum supply line to the canister with the engine running. Should have VACUUM at that line if its properly connected to the manifold and not damaged..
Bill
Thread Starter
Pro
Joined: Aug 2005
Posts: 503
Likes: 50
From: Bradenton, FL
I don't know of any way to get to it there other than to remove the manifold. I've had mine off twice, once for the oil pressure sender, the second to relocate the oil pressure sender, add insulation under the manifold and to add rear coolant air bleed lines. A good time to do everything back there including extending the vacuum tube enough to make re installation of the manifold easier.
You really need to remove the intake. Be prepared to extend the vacuum line to make it easier to work with. That short line that the factory provided sucks!
The line is nylon and can crack/rot and leak. If that's the case, be prepared to run all new line.
You can test the vacuum supply line to the canister with the engine running. Should have VACUUM at that line if its properly connected to the manifold and not damaged..
Bill
The line is nylon and can crack/rot and leak. If that's the case, be prepared to run all new line.
You can test the vacuum supply line to the canister with the engine running. Should have VACUUM at that line if its properly connected to the manifold and not damaged..
Bill
Drifting
Joined: Sep 2009
Posts: 1,862
Likes: 594
From: Prescott, Arizona
When I relocated the sender, I added a mechanical pressure gauge which can be read with the hood open. If a sender fails in the future I will be able to confirm (or not) that the engine still has oil pressure. And, of course changing the sender is a simple 5 minute job.
I'll send a picture if you wish-
Here is info on the insulation:
https://www.summitracing.com/parts/h...SABEgI2NfD_BwE
I'll send a picture if you wish-
Here is info on the insulation:
https://www.summitracing.com/parts/h...SABEgI2NfD_BwE
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote