What does this do??
Thread Starter
Melting Slicks
Joined: Feb 2001
Posts: 3,376
Likes: 4
From: Hershey, PA, USA
Cruise-In VI Veteran
St. Jude Donor '12
What does this do??
What does that vaccum line that runs from the back of the automatic tranny to the intake manifold do? I just put on my Edelbrock Pro-Flow and there is no vaccum port for the tranny. So I ran the car and it runs fine w/ out it. Is this bad for it and what the heck is it there for? :confused:
Race Director
Joined: Nov 2000
Posts: 16,416
Likes: 1
From: NC,USA
Re: What does this do?? (DCBStingray)
its on the passagner side right?? if it is, it is the vacum acutator that tells the trans to shift... some of the other guys on here can explain it better than I, my ears are open too
ZD
ZD
Thread Starter
Melting Slicks
Joined: Feb 2001
Posts: 3,376
Likes: 4
From: Hershey, PA, USA
Cruise-In VI Veteran
St. Jude Donor '12
Re: What does this do?? (DCBStingray)
Yeah it is on the passangers side.
But it will still shift even w/ it not hooked up. I thought it might be something to w/ the trans shift too.
But it will still shift even w/ it not hooked up. I thought it might be something to w/ the trans shift too.
Safety Car
Joined: Aug 2000
Posts: 3,711
Likes: 43
From: San Antonio TX
Re: What does this do?? (DCBStingray)
It's your vacuum shift modulator. It controls part-throttle (read as anything less than flooring it to engage the kickdown solenoid) upshifts that aren't controlled by the electronic kickdown, and your auytomatic downshifts. It works in concert with the governor. If you notice no difference in shift timing or harshness relative to the throttle with the modulator connected or not, then your modulator is frozen or has a ruptured diaphram.
Team Owner
Joined: May 2001
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From: Exiled to Richmond, VA - Finally sold my house in Murfreesboro, TN ?? Corner of "Bumf*&k and 'You've got a purdy mouth'."
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CI-VIII Burnout Champ
St. Jude Donor '06-'10, '13
Re: What does this do?? (gerry72)
You should use a vacuum tester on that line and make sure that the module on the tranny is not ruptured.
The reason you did not notice a difference as it was probably never working since you bought the car.
Replace the module and hook up some vacuum to this line and you will see a difference in the way the car behaves.
The reason you did not notice a difference as it was probably never working since you bought the car.
Replace the module and hook up some vacuum to this line and you will see a difference in the way the car behaves.
Team Owner
Joined: Dec 2000
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From: Swords Check/Saws Check/Clubs Check/Claws Check/Hatred Check/Anger Check/Murmaid Check/Murder Check
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Cruise-In VI Veteran
Re: What does this do?? (Vetteboy)
yeah.. i knocked mine off too after detailing my engine. Engine wouldn't upshift til about 4500 RPM and when it did it shifted HARD
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