Throttle Valve Cable/Linkage: Description and Operation

Throttle Valve (TV) Control Cable System:

Components
The Throttle Valve (TV) control cable system consists of a cable attaching grommet on the throttle body throttle lever, the TV control cable assembly, the external TV control lever on the transmission, and the cable mounting brackets at the throttle body and transmission.

Operation
As the throttle is moved from idle to Wide-Open Throttle (WOT), the TV control cable pulls the transmission TV control lever from idle to WOT. Return of the cable and transmission lever toward idle is accomplished by the return spring on the transmission end of the cable assembly. This spring and the end of the cable assembly is protected by a flexible rubber boot. The transmission external TV control lever actuates the internal TV control mechanism which regulates the TV control pressure. The travel of this lever is controlled by stops internal to the transmission.

TV Control Cable
The TV control cable is set and locked to its proper length during initial assembly when the grooved pin on the upper end of the cable assembly is inserted in the grommet on the throttle body lever. To release the cable locking mechanism, it is necessary to pry the grooved pin out of the grommet and push out the white locking pin. The take-up spring at the end of the cable assembly tensions the cable and takes up the slack in the system. When the grooved pin is reinserted in the grommet, the white locking tab is pushed in, automatically locking the cable to its correct length. When the cable is locked, the take-up spring plays no part in the operation of the system.

Situations Requiring Readjustment
Under normal circumstances, it should not be necessary to alter or readjust the initial setting of the TV control cable. Situations requiring readjustment of the TV control cable include maintenance involving the removal and/or replacement of the throttle body, transmission, TV cable assembly, or installing a new main control assembly. Readjustment of the TV control cable would also be necessary to correct complaints of poor transmission shift quality that would have been caused by a misadjustment of the TV control cable.

When the TV control cable is properly set, the transmission TV control lever will be at its internal idle stop (lever to rear as far as it will travel) when the throttle lever is at its idle stop.

Idle Speed Affect on TV Control Cable
The Sequential Electronic Fuel Injection (SEFI) engine uses an air bypass type Idle Speed Control (ISC) that does not affect throttle position. Therefore, idle automatic setting does not affect TV cable adjustment.