Cherokee 4WD V6-173 2.8L VIN W 2-bbl (1985)
1.
Move the carpeting away from the passenger front seat toeboard to expose the MCU harness.
2.
Untape the two-terminal connector from the MCU harness.
3.
Connect jumper wire, P/N 318 6890, to the two-terminal connector and reinstall the carpet.
4.
Advance ignition timing 7~ from the setting indicated on the original Vehicle Emission Control Information label in the engine
compartment and reset the engine idle speed to the setting indicated on the same label.
5.
Install Vehicle Emission Control Information Update label, P/N EF 8980 000 743, next to the original label.
These adjustments apply to 1985 Eagle/Jeep, 49-State/California/Canada 4.2L models with automatic transmissions originally sold for principal use at
altitudes below 4,000 feet. Refer to the Vehicle Emission Control Information label to identify these vehicles.
NOTE:
Whenever these vehicles are returned to operation at altitudes below 4,000 feet, the MCU circuit jumper wire must be removed, the ignition
timing and engine idle speed must be reset to original specifications and the Vehicle Emission Control Information Update label removed.
On 1985 Eagle/Jeep, 49-State/California/ Canada 4.2L models with automatic transmission originally sold for operation at altitudes above 4,000 feet that
are being operated below 4,000 feet, the ignition timing should be retarded 7~ and engine idle reset. In addition, the MCU circuit jumper wire must be
disconnected and taped to the MCU harness.
1.
Move the carpeting away from the passenger front seat toeboard to expose the MCU harness.
2.
Disconnect the jumper wire from the twoterminal connector in the MCU harness and tape the connector securely to the harness.
3.
Retard ignition timing 7~ from the setting indicated on the original Vehicle Emission Control label in the engine compartment and reset engine
idle speed to the setting indicated on this same label.
4.
Install Vehicle Control Information Update label, P/N EF 8980 000 744, next to the original label.
These adjustments apply to 1985 Eagle/Jeep, 49-State/California/Canada 4.2L models with automatic transmission originally sold for principal use at
altitudes above 4,000 feet. Refer to the Vehicle Emission Control Information label in the engine compartment to identify these vehicles.
NOTE:
Whenever these vehicles are returned to operation at altitudes above 4,000 feet, the MCU circuit jumper wire must be reconnected, the ignition
timing and engine idle speed must be reset to original specifications and the Vehicle Emission Control Information Update label removed.
49-State/California/Canada 4.2L Engine Adjustment - Manual Transmission
On 1985 Eagle/Jeep, 49-State/California/ Canada 4.2L models with manual transmission originally sold for operation at altitudes below 4,000 feet that
are being operated above 4,000 feet, the ignition timing must be advanced 7~, engine idle speed reset, and a jumper wire added to the MCU circuit. In
addition, the idle/ decel switch must be connected to the carburetor EGR port instead of the spark port.
1.
Move the carpeting away from the passenger front seat toeboard to expose the MCU harness.
2.
Untape the two-terminal connector from the MCU harness.
3.
Connect jumper wire, P/N 318 6890, to the two-terminal connector and reinstall the carpet.
