Anyone Have a Vacuum Control Module?
Thread Starter
Instructor
Joined: Jan 2007
Posts: 195
Likes: 2
From: Wilmington MA
Anyone Have a Vacuum Control Module?
Howdy,
I have an 81 and am having trouble changing from def/heat/vent. I have tracked it to the vacuum control switch which is the one connected to the heater control panel and has the rubber washer that selects which vacuum port to open to the source. The vacuum hose cluster pushes onto it. I have tried two new import units, both dont work.
Wondering if anyone has a new or used one that is GM original that you know works that you could part with?? 77-82 are supposed to be the same.
I dont believe the pattern on the imports channel the vacuum to the right heat/def/vent/ac ports.
Has anyone else had trouble in this area?
Frank
I have an 81 and am having trouble changing from def/heat/vent. I have tracked it to the vacuum control switch which is the one connected to the heater control panel and has the rubber washer that selects which vacuum port to open to the source. The vacuum hose cluster pushes onto it. I have tried two new import units, both dont work.
Wondering if anyone has a new or used one that is GM original that you know works that you could part with?? 77-82 are supposed to be the same.
I dont believe the pattern on the imports channel the vacuum to the right heat/def/vent/ac ports.
Has anyone else had trouble in this area?
Frank
Le Mans Master
Joined: Jan 2006
Posts: 9,192
Likes: 27
From: Boca Raton Florida
Ecklers sells them. I would try to fix it first unless its busted. Drill out the rivit that holds it together, clean it up and apply a very small amount of silicone grease and reassemble with a screw and nylock nut
Thread Starter
Instructor
Joined: Jan 2007
Posts: 195
Likes: 2
From: Wilmington MA
Thanks,
Tried re-assembling w grease and locknut. Still doent work. Seems like its not leaking, just not channeling the vacuum.
Anyone know what min vacuum is required to operate the system? On the possability that this aftermarket Performer intake is not producing enough vacuum to operate. Vacuum for this sysytem generated from a nipple behind the carb, on the intake and measures just above 20 on this one.
Does this sound right?
Thanks in advance,
Frank
Tried re-assembling w grease and locknut. Still doent work. Seems like its not leaking, just not channeling the vacuum.
Anyone know what min vacuum is required to operate the system? On the possability that this aftermarket Performer intake is not producing enough vacuum to operate. Vacuum for this sysytem generated from a nipple behind the carb, on the intake and measures just above 20 on this one.
Does this sound right?
Thanks in advance,
Frank
Thread Starter
Instructor
Joined: Jan 2007
Posts: 195
Likes: 2
From: Wilmington MA
Thanks,
I have the same at the switch, just above 20. And when i jump out the control module and supply each of the other vac lines seperatly w the source, all works fine. When all hooked to vac switch, always comes out the lower heater vents no matter the position of the switch.
Checked all hoses and diaphram modules, all ok.
Frank
I have the same at the switch, just above 20. And when i jump out the control module and supply each of the other vac lines seperatly w the source, all works fine. When all hooked to vac switch, always comes out the lower heater vents no matter the position of the switch.
Checked all hoses and diaphram modules, all ok.
Frank
