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jumping on this - I have a new to me 2001 chev express 8L - motorhome
replacing the same vacuum lines and check valve - question is the connection from the cab through the firewall has two connectors - cant for the life of me find where the 2nd one goes? Should there be a T in the line from the resevoir tank by the battery?
Last edited by mountainmanjoe; Aug 9, 2024 at 1:41 PM.
Sorry for the late reply. I replaced the 3-way check valve with no effect on the issue. This past week while changing spark plugs, I checked the new vacuum hoses...all good. I did notice this valve atop the intake manifold with the red seal. I'm able to pull it out and it will not retract on its own. What is it??
Mystery Valve
This is the vacuum hose attached to the intake manifold, routed to the engine compartment: Vacuum Hose
Thanks for the quick replies Gents. The rotted hose was literally falling apart in my hands...nasty black residue as well. Yesterday I checked the valve to make sure I hadn't mis-routed the tubing, but it appears correct to me. The black end of the T that goes to the manifold is one-way. I did a test drive, getting the same result. Arrrrggghhiie!
I do have a long-standing issue where the a/c doesn't get cold unless it's been running a few minutes, despite having a good charge. Not sure if these two issues are related. I did check the hoses in the passenger footwell and everything seems connected, but I am not an expert on these HVAC systems.
I just started a thread about this. I wanted to know what that third vacuum line went. As I suspected it goes into the cabin to the HVAC control. Now I have to find where this
vacuum line goes through the firewall and connect inside the cabin. Any input about this vacuum line would be appreciated.
I just started a thread about this. I wanted to know what that third vacuum line went. As I suspected it goes into the cabin to the HVAC control. Now I have to find where this
vacuum line goes through the firewall and connect inside the cabin. Any input about this vacuum line would be appreciated.
After further looking into this the third vacuum line is about the size of a #10 wire and appears to be plastic. Probably not going to even
mess with it or the valve. Just replace the line from the intake and the line to the reservoir.
