A/C & HEATER MODULE OPERATION AND DESIGN CHANGE

HEATER MODULE AIR VALVE

VEHICLES AFFECTED: 1986 DELTA 88 WITH MANUAL A/C (60) -----------------

Beginning in 1986, a now A/C and heater module was used on the Delta 88 models with C60 (manuaI A/C), This new design is on the 1987 Delta 88 and Ninety-Eight models with C60 (manual A/C).

This new module employs an additional air valve, called the slave valve. The slave slave in vacuum actuated and controlled by the mode Selector vacuum switch. Refer to Fig. 1.

The slave valve is operational (open) in the "HEATER" and "DEF" modes. When open, the valve directs more air through the heater core resulting in higher discharge air temperatures.

Diagnosis for this valve will be found on page 8A-65-0 "Air Delivery" of the 1987 Firenza, Calais, Cutlass Ciera, Deltas, Ninety-Eight Chassis Service Manual.

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