Curious vacuum line into firewall
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Racer
Joined: Apr 2004
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New England Events Coordinator
Curious vacuum line into firewall
I have a vacuum line that is plugged (with a golf tee) that enters the engine bay through the firewall just behind the vacuum advance module. Can anyone help explain where this line should connect to on the engine? What does it function?
1970 350/300hp vert
1970 350/300hp vert
Team Owner
Joined: Sep 2006
Posts: 31,266
Likes: 4,355
From: Westminster Maryland
Hi phc,
From your description I believe that's the vacuum supply for the heater/defroster control in the shifter console. It's a small 1/8" line if it's the one I'm thinking of. It T's into the vacuum supply near the right side hood latch bumper. I'm not sure if 70 has the connection there or not. Just trying.
Regards,
Alan
From your description I believe that's the vacuum supply for the heater/defroster control in the shifter console. It's a small 1/8" line if it's the one I'm thinking of. It T's into the vacuum supply near the right side hood latch bumper. I'm not sure if 70 has the connection there or not. Just trying.
Regards,
Alan
Team Owner
Joined: Sep 2006
Posts: 31,266
Likes: 4,355
From: Westminster Maryland
Hi phc,
It T's in to the large yellow striped vacuum supply hose.
WAIT.... where is the 'wiper door relay' located on your 70... on the side of the firewall near the master cylinder or is it behind the right side wheel well? In 71 it's behind the wheel well, but in 70 I don't think it is.
The 'T' has to be in a large yellow striped hose since that's the source of vacuum for the actuators, not in the the small hoses that are the vacuum source for the relays.
Regards,
Alan
It T's in to the large yellow striped vacuum supply hose.
WAIT.... where is the 'wiper door relay' located on your 70... on the side of the firewall near the master cylinder or is it behind the right side wheel well? In 71 it's behind the wheel well, but in 70 I don't think it is.
The 'T' has to be in a large yellow striped hose since that's the source of vacuum for the actuators, not in the the small hoses that are the vacuum source for the relays.
Regards,
Alan
Intermediate
Joined: May 2024
Posts: 48
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From: San Jose, CA
I need this T!
Hi phc,
From your description I believe that's the vacuum supply for the heater/defroster control in the shifter console. It's a small 1/8" line if it's the one I'm thinking of. It T's into the vacuum supply near the right side hood latch bumper. I'm not sure if 70 has the connection there or not. Just trying.
Regards,
Alan
From your description I believe that's the vacuum supply for the heater/defroster control in the shifter console. It's a small 1/8" line if it's the one I'm thinking of. It T's into the vacuum supply near the right side hood latch bumper. I'm not sure if 70 has the connection there or not. Just trying.
Regards,
Alan
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From: Sunshine Coast, Queensland, Australia
2025 C3 of the Year Finalist - Modified
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You realise this thread is 14 years old. Please start a new thread asking your question. Alan hasn't been on the forum in nearly a year.
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....miss him much,,,he was the first person to reply to my rookie thread in 2013.
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From: US-PNW
(I see he copy/pasted one of my last replies about this fitting to the item's page
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