High Altitude Driveability Modifications
Article No: 82-11A-9June 4, 1982
Subject:
Modification Of Sea Level Calibrations For Altitude Applications
Light Trucks
1982 Bronco, E And F Series Under 8500 Lb. GVW With 4.2L And 5.0L Engines Except California
WARNING: This Modification Is Authorized Only For The Listed Engine Calibration. Performing This Modification On Other Engine Calibrations Is Unauthorized And Could Create Liability Under Applicable Federal Or Local Laws.
Customers who may have relocated and/or continually operate the subject vehicles in high altitudes (above 4,000 ft. alt.) may have the following procedure performed to improve performance:
4.2L Engines
1. Replace PCV valve (Part No. D9BZ-6A666-A) with a new PCV valve (D8TZ-6A666-B).
2. Remove air pump pulley (Part No. D9UZ-9B447-A). Install new pulley (Part No. D5FZ-9B447-D) by referring to procedure outlined in pertinent Truck Shop Manual.
3. Remove air pump drive belt (Part No. D9PZ-8620-C). Install new belt (Part No. D5PZ-8620-C) and tension to 120-160 lbs..
4. Advance ignition timing 4 ° from specification on Vehicle Emission Control Decal by referring to procedure outlined in pertinent Truck Shop Manual.
5. Remove existing transmission vacuum diaphragm and install altitude compensating diaphragm and clip (Part No. D7DZ-7A377-A & D7FZ-7F006-A).
NOTE:
Step 5 does not apply to manual transmission vehicles.
6. Check and reset idle speeds, if necessary, per Vehicle Emission Control Decal.
7. Obtain a Vehicle Emission Control Information Update Label (available at all Ford or Lincoln-Mercury dealers) and fill in the appropriate information as indicated on page 2.
If the vehicle is returned to continuous sea level (below 4,000 ft. alt.) operation, the above procedures should be reversed and the Vehicle Emission Control Information Update Label should be removed from the vehicle.
NOTE:
The parts list includes part numbers for the original sea level components to aid in returning the vehicle to sea level operation. The transmission diaphragm will not require replacement because the altitude diaphragm is self-compensating.
5.OL Engines
1. Replace the PCV valve (Part No. D9ZZ-6A666-A) with a new PCV valve (Part No. D90Z-6A666-A).
2. Remove original air pump pulley (EOTZ-9B447-A). Install new pulley (Part No. D5FZ-9B447-D) by referring to procedure outlined in pertinent Truck Shop Manual.
3. Remove original air pump drive belt. Install new belt (Part No. D5PZ-8620-C used with 40-60 amp. alternator) or (Part No. E0PZ-8620-A used with 70-100 amp. alternator) and tension to 120-160 lbs..
4. Advance ignition timing 4 ° from specification on Vehicle Emission Control Decal by referring to procedure outlined in pertinent Truck Shop Manual.
5. Remove existing transmission vacuum diaphragm and install altitude compensating diaphragm * (Part No. D8AZ-7A377-A C6 transmission) as outlined in the Light Truck Chassis Manual 17-01-22.
Note:
The attaching vacuum hose must be shortened by 3/4 inch. Step 5 does not apply to manual or A0D transmission vehicles.
6. Check and reset idle speeds, if necessary, per Vehicle Emission Control Decal.
Obtain a Vehicle Emission Control Information Update Label (available at all Ford or Lincoln-Mercury dealers) and fill in the appropriate information as indicated on page 2.
(5.OL)
If the vehicle is returned to continuous sea level (below 4,000 ft. alt.) operation, the above procedures should be reversed and the Vehicle Emission Control Information Update Label should be removed from the vehicle.
NOTE:
The parts list includes part numbers for the original sea level components to aid in returning the vehicle to sea level operation. The transmission diaphragm will not require replacement because the altitude diaphragm is self- compensating.
Parts Block
WARRANTY STATUS: Reimbursable within the provisions of the Warranty and Policy Manual.
OPERATION: SP 689O-B-B1
TIME:
1.3 Hrs. Econoline
1.0 Hrs. F & Bronco with Standard & AOD Transmission
1.2 Hrs. F & Bronco with C5/C6 Transmissions
DLR. Coding:
Basic Part No. Code:
L05 53