Q: The 305 was rebuilt and all vacuum lines and sending units were removed. An old style hei distributor was used to replace the one that needs a computor.the problem is the tranny will not shift into 3rd.
Is this condition due to some kind of input from the engine the tranny needs to know to allow it to shift?
Other than this problem everything runs great. If it needs something from an engine sensor which one?
A: CHECK THAT YOU HAVE VACCUM TO THE MODULATER VALVE ON TRANNY.