Engine - High Altitude Modifications
88mitsubishi03SUBJECT:
HIGH ALTITUDE MODIFICATIONS- 1989 TRUCKS AND MONTERO
NO. TSB-88-25-001
DATE July, 1988
MODEL 1989 Truck and Montero
PURPOSE 1989 Truck (2.0L and 2.6L engine) and Montero (2.6L engine only) vehicles distributed to high-altitude market areas must be modified for high-altitude operation by the dealer before sale. Modifications consist of advancing the ignition timing and installing a High Altitude Compensator (HAC), vacuum hose assembly, underhood label and replacing the distributor vacuum advance mechanism.
VEHICLES TO BE MODIFIED 1989 model Truck and Montero vehicles, 2-wheel drive and 4-wheel drive models, 2.0L and 2.6L engines only. The 3.0L engine (V6) used in the Montero has been certified for all altitudes and requires no modification.
GEOGRAPHIC APPLICATION If a 1989 vehicle's ultimate intended use in one of the following high altitude states and counties, it must be equipped with a high altitude kit.
HIGH ALTITUDE STATES AND COUNTIES
State of Arizona
Apache Navajo
Cochise Yavapai
Coconino
State of Colorado All counties
State of Idaho
Bannock Franklin
Bear Lake Fremont
Bingham Jefferson
Blaine Lemhi
Bonneville Madison
Butte Minidoka
Camas Oneida
Caribou Power
Cassia Teton
Clark Valley
Cluster
State of Montana
Beaverhead Madison
Deer Lodge Meagher
Gallatin Park
Jefferson Silver Bow
Judith Basin Wheatland
Powell
State of Nebraska
Banner Kimball
Cheyenne Sioux
State of Nevada All counties
State of New Mexico All counties
State of Oregon
Harney Klamath
Lake
State of Texas
Jeff Davis Parmer
Hudspeth
State of Utah All counties
State of Wyoming
Albany Natrona
Campbell Niobrara
Carbon Park
Converse Platte
Fremont Sublette
Goshen Sweetwater
Hot Springs Teton
Johnson Uinta
Laramie Washakie
Lincoln Weston
WARRANTY INFORMATION
Labor Operation Code: 25 05 30 01
Time Allowance: 0.7 hr.
PARTS INFORMATION Four kits are available as follows:
Kit Components
The following components are contained in all kits except as noted.
PART NAME QUANTITY
Compensator, High Altitude 1
Hose Assembly, Vacuum 1
Bracket, HAC 1
Bolt, Washer Assembled 2
Vacuum Assembly, Distributor 1
E-Clip (2.0L Truck Only) 1
Label, Emission Update 1
MODIFICATION PROCEDURE
1. Replace the distributor vacuum assembly with the new part in the kit as described in the Service Manual. On the distributors of 2.0L Truck engines, install a new E-clip from the kit.
2. Make sure the ignition timing is set to the correct specification as follows:
a. Remove and plug the vacuum hoses on the distributor.
b. Set ignition timing to the specifications shown below.
ENGINE TIMING SPECIFICATION
2.0L 8~ + 2~ BTDC
2.6L 7~ + 2~ BTDC
c. Reconnect the vacuum hoses to the distributor. The High Altitude Compensator will automatically advance the timing approximately 5~ if at high altitudes.
FIGURE 1 HAC AND VACUUM HOSE INSTALLATION FOR TRUCK 2.0L AND 2.6L ENGINES.:
FIGURE 2 HAC AND VACUUM HOSE INSTALLATION FOR MONTERO 2.6L ENGINE.:
FIGURE 3:
4. Install the High Altitude Compensator (HAC) and vacuum hose assembly as follows:
a. Install the HAC bracket on the Device Box in the engine compartment. Use the 2 bolts from the kit. See Figures 1 and 2.
b. Remove the rubber caps from the carburetor (Figure 3) and Device Box (Figures 1 and 2).
c. Install the vacuum hoses as indicated in the appropriate illustration.
FIGURE 4:
5. Apply the Vehicle Emissions Control Information Update Label on the underside of the hood in the location shown in Figure 4.