Component Testing
- Make sure all vacuum hoses and heat cowl to air cleaner air duct are properly attached and in good condition. With engine cold and ambient temperature less than 84°F (29°C), the air control valve should be in up (heat on) position.
- With engine at normal operating temperature, check air temperature entering outer end of snorkel. When air entering snorkel is 113°F (45°C) or higher, valve should be in down (heat off) position.
- Remove air cleaner from engine and allow to cool to 84°F (30°C). With 15 in. Hg vacuum applied to sensor, valve should be in up (heat on) position. If valve door does not move to up (heat on) position, check vacuum motor for proper operation.
- To test vacuum motor, apply 10 in. Hg vacuum with vacuum pump. Valve should be in full up position. If vacuum motor is not okay, replace air cleaner assembly.