Cherokee 2WD L4-126 2.1L DSL Turbo VIN B FI (1986)
Ignition Timing: By Symptom
Engine - Altitude Performance Adjustment
OCTOBER 1985 000 816
1986 AMC/JEEP/RENAULT MODELS
35E
ENGINES
Attention: Workshop, Parts Department
ALTITUDE PERFORMANCE ADJUSTMENTS
This I.S. Note outlines adjustment for optimum engine performance on 1986 AMC/Jeep/Renault models being operated at high or low altitudes.
When necessary, perform the engine adjustments outlined in this I.S. Note. In addition, any 1986 model that is so adjusted must have a unique Emission
Control Information Update label installed. The part numbers for these unique labels are provided in the adjustment procedures outlined in this I.S. Note.
The adjustment procedures and unique labels must be made available at no cost to independent repair facilities and the general public. A notification is
also provided in current owner manuals to make the owner aware of these adjustments. The Emission Control Information Update labels and technical
information are available from:
Myriad 8835 General Drive Plymouth, MI 48170 1-800-AMC-CARS Operator 43
CONTENTS
1.
1986 Alliance/Encore 1.4L - 1.7L Engines and Sportwagon 2.2L Engines
2.
1986 Cherokee/Wagoneer/Comanche 2.8L Engines, 2.46L Engines With Throttle Body Injection and 2.1L Turbo-Diesel Engines
3.
1986 CJ 2.46L Carburetor Equipped Engines
4.
1986 Eagle/CJ/Grand Wagoneer/Truck 4.2L Engines
5.
1986 Grand Wagoneer/Truck 5.9L Engines
FILING INSTRUCTIONS
Record this I.S. Note on the index page of Chapter B, Engines, in the appropriate M.R. manual.
1.
1986 ALLIANCE/ENCORE 1.4L-1.7L ENGINES AND SPORTWAGON 2.2L ENGINES
1986 Alliance/Encore 1.4L - 1.7L engines and Sportwagon 2.2L engines do not require adjustment. The electronic control systems on these engines
have built-in compensating circuits that make necessary adjustments automatically.
2.
1986 CHEROKEE/WAGONEER/COMANCHE 2.8L ENGINES, 2.46L ENGINES WITH THROTTLE BODY INJECTION AND 2.1L
TURBO-DIESEL ENGINES
For 1986, only the Cherokee/Wagoneer/ Comanche, 49-State and Canada 2.8L gasoline engine requires adjustment as outlined below. The 1986
49-State and Canada 2.1L TurboDiesel engine, 1986 California 2.8L gasoline engine, and 1986 49-State and California 2.4 engine with throttle
body injection do not require adjustment. The fuel metering control systems on these engines have built-in compensating devices that make
necessary adjustments automatically. The 2.8L engine adjustments are as follows.
Adjustment - 49-State and Canada 2.8L Engines
On 1986, 49-State and Canada Cherokee/ Wagoneer/Comanche 2.8L models 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.
1.
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.
2.
Install Vehicle Emission Control Information Update label, part number EF 8980 000 818, next to the original label.
This adjustment applies to 1986 Cherokee/ Wagoneer/Comanche, 49-State and Canada 2.8L 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 ignition timing and engine idle speed must be reset to
original specifications and the Vehicle Emission Control Information Update label removed.
On 49-State and Canada 1986 Cherokee/ Wagoneer/Comanche 2.8L models sold for operation at 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.
