That is a better way to go, 
Hard Shift?
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From: Eustis ( Area 51 Bat Cave ) Fl
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From: Eastern Ky
I put OBX stainless side exhausts on my 78. Been on there a couple of years and are working great. Do a search on Ebay. I put them on myself in a couple of evenings and I'm 73. (Check my avatar picture) Good luck and keep us posted,
Advanced
Joined: Sep 2013
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From: Pflugerville Texas
Dang, I thought that would fix your problem. You checked the vacuum line up at the manifold and didn't find any issues there? Does the car seem to be idling fine? If the idle is high then your still chasing a vacuum leak.
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Thread Starter
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Joined: Jan 2015
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when it shifts down i don't speed up i slow down. but i traced the vacuum modulator up to the intake and i found a T where it connected and i move the T a bit and it completely disintegrated. im gonna try to replace that and hopefully that was the problem.
Team Owner
Joined: Aug 1999
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From: Ontario
I am having a hard time imagining what setup you have at the back of the intake that would need the plastic adapter. The transmission and headlamp vacuum should come from a "metal" fitting screwed into the back of the intake (pic shows one I use but they vary from year-to-year). Brake vacuum comes from a metal tubing screwed into the back of the Q-Jet. Can you post a pic of what you have?
Last edited by Paul L; Feb 8, 2015 at 04:03 PM.
Thread Starter
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that T looks like what should be there. i think the previous owner may have just putt a threaded nipple in and put a hose on it then the T i currently have on it. yeah ill get a pic of the intake on here.
Pro
Joined: May 2013
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From: Rapid City South Dakota
I'm going to suggest a possible vacuum leak. If the transmission kicks down due to throttle position, it will downshift but as RPM increases so do the effects of improper air/fuel ratio due to increased vacuum leaks resulting in power loss.
I've seen mechanics use propane torches around vacuum lines and fittings to detect an increase in RPM indicating the propane was being sucked in and burned instead of the air, which can cause rough idle etc. (the propane torch should not be lit, of course)
All my transmission failures have been slipping between gears, or all out failure meaning the car won't move. I doubt you need a new transmission, and the miles of old vacuum lines are very suspect....
I've seen mechanics use propane torches around vacuum lines and fittings to detect an increase in RPM indicating the propane was being sucked in and burned instead of the air, which can cause rough idle etc. (the propane torch should not be lit, of course)
All my transmission failures have been slipping between gears, or all out failure meaning the car won't move. I doubt you need a new transmission, and the miles of old vacuum lines are very suspect....
Last edited by lurch59; Feb 9, 2015 at 06:04 PM. Reason: forgot a point