Broken Vacuum Lines
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From: Broken Arrow, OK
Broken Vacuum Lines So the small plastic vacuum lines that come off of the back of the intake that run to the HVAC and EVAP systems on my car are broken. And I don't know why but I CAN NOT find replacement ones. So I was wondering if anyone had some information on where to find replacements? And if that isn't possible I was going to buy some 1/8" vacuum tubing and just make my own. Has anyone heard of doing this and if so will it work? Any insight would be greatly appreciated.
I'm wondering why the originals are hard plastic vs. rubber. (I haven't been able to figure that one out.)
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From: Broken Arrow, OK
Well the one that feeds the HVAC broke around 110k miles and the EVAP one broke around 122k. Both were my fault and happened when doing maint/mods. Thats the only reason I wouldn't want to go back together with the plastic ones. It just seems to me those things are just waiting to break.
Rubber degrades under the fumes that float around the intake manifold. That's the only reason I can think of. Only other reason would be heat resistance or price lol. We know GM is cheap where it can be...
I've always been intrigued by this question. My expectation has always been that:
- The hard plastic lines are more expensive than the traditional soft rubber.
- GM had a chafing or clearance issue and had to go to the thinner lines.
- There is more of a pressure drop in a longer rubber hose vs. the plastic.
- The hard plastic lines are more expensive than the traditional soft rubber.
- GM had a chafing or clearance issue and had to go to the thinner lines.
- There is more of a pressure drop in a longer rubber hose vs. the plastic.
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From: Broken Arrow, OK
The only thing I was wondering is how much vacuum is pulled on these lines and could it possibly collapse the hose. I suppose I will find out one way or another.
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From: Broken Arrow, OK
Update: I replaced my broken plastic lines with some 1/8 rubber hose from the parts store and it didn't fix my hvac selector. I'm not sure if it's in the hose itself or if I don't have a secure enough connection some where in the system. Hopefully I can find it before the weather gets too warm.
They are handy for everything. Testing vacuum lines, (confirm if they lines hold a vacuum) bleeding brakes, siphoning fluids, etc. I even use mine in the kitchen (with sterile attachments!) do dip cookies in chocolate during the holidays. (If that creates a Martha Stewart vision for you, I hope you can erase that from your memory.)
I recall that they are $25-$35 or the basic systems. (The lower end units are all plastic, which is what I have and the higher end pumps have a metal cylinder.)
Mighty Vac also sells seal/valve kits that you can use to rebuild the pumps - even the plastic ones.
Mighty Vac also sells seal/valve kits that you can use to rebuild the pumps - even the plastic ones.
So the small plastic vacuum lines that come off of the back of the intake that run to the HVAC and EVAP systems on my car are broken. And I don't know why but I CAN NOT find replacement ones. So I was wondering if anyone had some information on where to find replacements? And if that isn't possible I was going to buy some 1/8" vacuum tubing and just make my own. Has anyone heard of doing this and if so will it work? Any insight would be greatly appreciated.
I reached behind the manifold and their was a 1/8 plastic line with a rubber boot on the end of it not attached to anything, almost like a spark plug wire.
Is this the HVAC line that would cause my problem?
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From: Broken Arrow, OK
Do you have a picture of the line? My ac is not working, only blowing air out top and bottom.
I reached behind the manifold and their was a 1/8 plastic line with a rubber boot on the end of it not attached to anything, almost like a spark plug wire.
Is this the HVAC line that would cause my problem?
I reached behind the manifold and their was a 1/8 plastic line with a rubber boot on the end of it not attached to anything, almost like a spark plug wire.
Is this the HVAC line that would cause my problem?
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From: Broken Arrow, OK
UPDATE: well during my motor rebuild I went to the local parts store and bought some 5/32" hard plastic vacuum/emission tubing similar to the factory stuff and ran all new tubing from the back of the intake to the junction where the lines split off and still no luck.
It will however blow from the vents around 3k rpms?... so I'm guessing I've still got a leak somewhere. I did buy a mityvac to bleed my brakes so when I get a chance I'm going to go test my lines. Just wanted to update for anyone having the same problem.
It will however blow from the vents around 3k rpms?... so I'm guessing I've still got a leak somewhere. I did buy a mityvac to bleed my brakes so when I get a chance I'm going to go test my lines. Just wanted to update for anyone having the same problem.
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From: Broken Arrow, OK
UPDATE: well during my motor rebuild I went to the local parts store and bought some 5/32" hard plastic vacuum/emission tubing similar to the factory stuff and ran all new tubing from the back of the intake to the junction where the lines split off and still no luck.
It will however blow from the vents around 3k rpms?... so I'm guessing I've still got a leak somewhere. I did buy a mityvac to bleed my brakes so when I get a chance I'm going to go test my lines. Just wanted to update for anyone having the same problem.
It will however blow from the vents around 3k rpms?... so I'm guessing I've still got a leak somewhere. I did buy a mityvac to bleed my brakes so when I get a chance I'm going to go test my lines. Just wanted to update for anyone having the same problem.