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Home >> Volkswagen >> 1991 >> Jetta L4-1781cc 1.8L SOHC >> Repair and Diagnosis >> Specifications >> Mechanical Specifications >> Powertrain Management >> Computers and Control Systems >> System Specifications >> California
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California

Air/Fuel Ratio
Adjustment specification [1] 0.7%
Checking limits 0.3 - 1.2%

IDLE SPEED [1]
When Hot 750 - 850 RPM

IGNITION TIMING [1]
2250 ± 50 RPM Coolant temperature sensor disconnected
Checking 4° - 8° BTDC
Adjust to 6° - 1° BTDC

FIRING ORDER 1 - 3 - 4 - 2

Oxygen Sensor
Torque 37 ft.lbs (50 Nm.)


[1] Ignition timing, idle speed and CO need to be adjusted together to prevent driveablity problems. For complete procedure, see COMPUTERS AND CONTROL SYSTEMS/ADJUSTMENTS. Adjustments
Clear fault memory codes after disconnecting and reconnecting the coolant temperature sensor. If the base ignition timing has been changed, the control unit must be returned to reference settings. Refer to COMPUTERS AND CONTROL SYSTEMS/ENGINE CONTROL MODULE/ADJUSTMENTS Adjustments