Cold Engine Operation

When engine intake air temperature is below 86°F (30°C) on Pickup and Stanza, or below 100°F (38°C), on Pulsar and Sentra models, sensor air bleed valve is closed.

This allows intake manifold vacuum to vacuum motor. With vacuum applied to vacuum motor, air control valve, attached to vacuum motor diaphragm, is opened. This allows hot air into air cleaner through hot air duct on exhaust manifold.