The General Motors throttle valve cable connects the carburetor or throttle body to the transmission. The TV cable is not an adjustment for transmission downshifts, but, when set properly, controls line pressure, shift points, part throttle downshifts and the detent downshifts by directing hydraulic pressure and volume through the correct passage. The cable is similar to the combined functions of a vacuum modulator and a detent cable. Having it set correctly eliminates many transmission problems
Shut off the motor and open the hood. Locate the TV cable assembly. It is connected to the carburetor or throttle body in conjunction with the throttle linkage from the accelerator pedal. The TV cable is attached underneath the accelerator cable in such a way that as the accelerator opens the throttle, the TV cable is pulled and that operates the valve body in the transmission. Once located, spray with cleaner and wipe with a rag.
Examine the TV cable assembly and notice that it has a plastic release tab behind the hold-down fitting. Depress and hold down the readjust tab. Move the slider through fitting away from the lever assembly, until the slider stops against the fitting. Release the readjust tab, then open the throttle lever to its full throttle position to automatically set the cable.
Release throttle lever and check the cable for sticking or binding. It might appear to function properly with engine stopped and cold. Recheck cable with the engine at normal operating temperature.
Road test the vehicle and check for proper shifting, downshifting and overall operation.
