Cavalier/Z24 L4-134 2.2L (1991)
Heater Control Valve: All Technical Service Bulletins
Heater - Low Output
Number: 91-413-1A
Section: 1A
Date: SEPT. 1991
Corporate Bulletin No.: 131104
ASE No.: A7
Subject:
LOW HEAT DELIVERY RELATED DIAGNOSIS REVISED PROCEDURE
Model and Year:
1989-91 CAVALIER
On customer comments of low heater output on 1989-91 J cars, before replacing a suspected defective engine cooling thermostat, proper diagnosis of the
condition must be performed to avoid the possibility of a repeat repair. Follow "Diagnosis" as shown in Section 1A/1B of the appropriate Service
Manual.
After completing the diagnosis, use the following as a guide to the next corrective step:
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If the diagnosis indicates a defective thermostat, refer to Section 6C for replacement.
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If the diagnosis indicates a defective temperature control cable, refer to Section 1A/1B for replacement.
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If the diagnosis indicates the temperature control cable is no longer "snapped" into its retainer, refer to "Temperature Control Cable Repair" in
the 1991 Service Manual, Sections 1A/1B.
^
If the diagnosis indicates that the temperature control cable is out of adjustment, refer to the following procedure to repair.
TEMPERATURE CONTROL CABLE ADJUSTMENT PROCEDURE
Condition:
1. "Spring back" off full "hot" temperature control position (or not attaining full "cold" temperature door position).
Condition:
2. "Spring back" off full "cold" temperature control position (or not attaining full "hot" temperature door position).
Cause:
The temperature control cable "clip" needs adjustment. Refer to the illustration for correct gripping of the "clip" during adjustment.