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Won't shift w/o racing it.

595 Views 3 Replies 2 Participants Last post by Guest, Mar 25, 2001

Discussion Starter · #1 · Mar 25, 2001

My C-4 will not shift between gears unless you really race the engine, and then it will dump into the next gear rather rough. I have heard the modulator may be bad, or the vacuum may not be there, I'm ready to check it out, and I want to know where to start. I want to do some crusing w/o wondering if it will shift! Tranny rebuild is not out of the question, right? (Leaks all over too)

1966 C-Code Convertible, 59 Edsel Villager
Charlotte, NC
New Cars Have No Soul.

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Joined Mar 21, 2001

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#3 · Mar 25, 2001

Your problem is the vacuum modulator. Either the vacuum line has came off or
the modulator is bad or not adjusted properly. See if the vacuum line is in good
condition, if it is, see if the modulator has a screw in the back where the line goes
on. Turning it in raises the rpm of the shift. Good Luck!