Cherokee 4WD V6-173 2.8L VIN W 2-bbl (1985)
This adjustment applies to 1985 Cherokee/ Wagoneer, 49-State/Canada 2.8L models that were 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 ignition timing and engine idle speed must be reset to
original specifications and the Vehicle Emission Control Information Update label removed.
3.1985 Cherokee/Wagoneer 70 Series - CJ/Scrambler 2.46L Engine
1985 Jeep California and 49-State/Canada 2.46L engines require adjustment as outlined below.
California - 49-State/Canada 2.46L Engine Adjustment
On 1985 AMC/Jeep California and 49-State/ Canada 2.46L models originally sold for operation at altitudes below 4,000 feet that are being operated
above 4,000 feet, the ignition timing as shown on the original Vehicle Emission Control Information label in the engine compartment, should be
advanced 7~ and engine idle speed reset to the specifications indicated on this same label. In addition, a jumper wire must be added to the MCU circuit
to activate the altitude compensating circuit in the MCU.
1.
Locate the MCU under the instrument panel, just to the right of the steering column.
2.
Locate the two-terminal connector on the MCU harness.
3.
Connect jumper wire, P/N 318 6890, to the two-terminal connector.
4.
Advance ignition timing 7~ from the setting indicated on the original Vehicle Emission Control Information label and reset 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.
This adjustment applies to 1985 Jeep California and 49-State/Canada 2.46L models that were originally sold for principal use at altitudes below 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 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 Jeep California and 49-State/Canada 2.46L models originally sold for operation altitudes above 4,000 feet that are being operated below 4,000
feet, the ignition timing as shown on the original Vehicle Emission Control Information label in the engine compartment should be retarded 7~ and
engine idle reset to the specification indicated on this same label. In addition, the MCU circuit jumper wire must be disconnected.
1.
Locate the MCU under the instrument panel to the right of the steering column.
2.
Disconnect the jumper wire from the twoterminal connector in the MCU harness and tape the connector securely to the harness. Place the jumper
wire in the glove box - do not discard it.
3.
Retard ignition timing 7~ from the setting indicated on the original Vehicle Emission Control label and reset engine idle speed to the setting
indicated on this same label.
4.
Install Vehicle Emission Control Information Update label, P/N EF 8980 000 744, next to the original label.
This adjustment applies to 1985 Jeep California and 49-State/Canada 2.46L models that were 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 operations 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.
4.1985 Eagle - CJ/Scrambler - Grand Wagoneer/Truck 4.2L Engine
For 1985, Eagle/Jeep 49-State/California/ Canada 4.2L engines require altitude adjustment. However, the method of adjustment for automatic or manual
transmission equipped models are different as outfined in the following procedures.
49-State/California/Canada 4.2L Engine Adjustment - Automatic Transmission
On 1985 Eagle/Jeep, 49-State/California/ Canada 4.2L models with automatic 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~ and engine idle speed reset. In addition, a jumper wire must be added
to the MCU circuit to activate the altitude compensating circuit in the MCU.
