Cherokee 2WD L4-126 2.1L DSL Turbo VIN B FI (1986)
1986 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.
1.
On Eagle models, move the carpeting away from the passenger side toeboard to expose the MCU harness. Untape the two-terminal connector from
the harness. Connect jumper wire, 318 6890, to the two-terminal connector and reinstall the carpet.
2.
On Jeep models, locate the black with tracer altitude circuit ground wire. The wire is in the MCU harness located near the ignition coil. Remove
the tape covering the eyelet on the ground wire and attach the eyelet to the engine ground screw near the ignition coil.
3.
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.
4.
Install Vehicle Emission Control Information Update label, part number EF 8980 000 818, next to the original label.
These adjustments apply to 1986 Eagle/Jeep, 49-State/California/Canada 4.2L models with automatic transmission, 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 reset to original specifications, and the Vehicle Emission Control Information Update label removed.
On 1986 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.
On Eagle models, move the carpeting away from the passenger side front toeboard to expose the MCU harness. Disconnect the jumper wire from
the two-terminal connector in the MCU harness and tape the connector securely to the harness. Then place the jumper wire in the glove box.
2.
On Jeep models, disconnect the black with tracer altitude circuit ground wire from the engine. Cover the ground wire eyelet with tape and secure
the wire to the MCU harness with tape or a tie strap.
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, part number EF 8980 000 819, next to the original label.
These adjustments apply to 1986 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 reset to original specifications, and the Vehicle Emission Control Information Update label removed.
Adjustment - 49-State/California/Canada 4.2L Models With Manual Transmission
On 1986 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 ground wire connected to the MCU circuit.
In addition, the idle/decel switch must be connected to the carburetor EGR port instead of the spark port.
1.
On Eagle models, move the carpeting away from the passenger side toeboard to expose the MCU harness. Untape the two-terminal connector from
the harness. Connect jumper wire, 318 6890, to the two-terminal connector and reinstall the carpet.
2.
On Jeep models, locate the black with tracer altitude circuit ground wire. The wire is in the MCU harness located near the ignition coil. Remove
the tape covering the eyelet on the ground wire and attach the eyelet to the engine ground screw near the ignition coil.
