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Won't shift w/o racing it.

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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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· Supporting Vendor
3,951 Posts
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!
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