Open Loop Control

During open loop control, the air/fuel ratio is determined by the ECC control unit. For improved driveability, air/fuel ratio solenoid is controlled by open loop control under the following conditions:

• When battery voltage is below 10 volts.
• When starting engine and cranking speed is below 400 RPM.
• On Pulsar and Sentra, when engine coolant temperature is below 122°F (50°C) for manual transmission or 140°F (60°C) for automatic transmission.
• On Pickup, when engine coolant temperature is below 95°F (35°C) for heavy duty models, or 122°F (50°C) for light duty models.
• When exhaust gas sensor is not activated.
• When driving at high speeds (above 3425 RPM for California Pulsar and Sentra, above 4150 RPM for Federal Pulsar and Sentra).