High Altitude Modifications
Article No: 82-11A-6June 4, 1982
Subject:
Modification Of Sea Level Calibrations For Altitude Applications
Ford
1982 Mustang, Fairmont, Granada, T-Bird With 4.2L Or 5.0L Engine And C-5, AOD Or SROD Transmission 49 States
Calibrations: 2-18B, 2-18C, 2-20D, 2-21E, 2-21S
Lincoln-Mercury
1982 Capri, Zephyr, Cougar, XR7 With 4.2L Or 5.0L Engine And C-5, AOD Or
SROD Transmission 49 States
Calibrations: 2-18B, 2-18C, 2-20D, 2-21E, 2-21S
Customers who may have relocated and/or continually operate the subject vehicles in high altitudes (above 4,000 ft. alt.) may have the following procedures performed to improve performance:
1. Remove the choke plate lever and reinstall the choke plate rod in the altitude position, stamped on the choke plate lever. (See Section 24-25- of the 1982 Car Shop Manual.)
2. Remove the existing vacuum delay valve (12A189)
(NOTE: None on Calibration 2-21S) and install a brown and black vacuum delay valve (part number D3DZ-12A091-B) in the hose routed to the thermactor air control valve, including calibration 2-21S. The control valve is of a dual diaphragm design and the delay valve is to be installed with the brown side facing the diaphragm that does not have vent holes. (Holes will show cotton fiber used for filtering ambient air.)
3. Vehicles equipped with C-5 or SROD Transmission only:
a. Set ignition timing to 4 ° advanced over sea level specification (to 14 ° BTDC on C-5 equipped and 16 ° BTDC on SROD equipped vehicles) referring to procedure outlined in Section 4 in the 1982 Car Shop Manual.
b. Vehicles equipped with AOD transmission only: Install a vacuum check valve (part no. D9AZ-12A197-A) in the hose routed to the ignition timing vacuum switch, mounted near the ignition module. Be sure the blue side of the vacuum check valve is facing the ignition timing vacuum switch.
4. Check to ensure all vacuum hose connections are secure and there are no vacuum leaks.
5. Obtain a Vehicle Emission Control Information Update Label (available at all Ford or Lincoln-Mercury dealers) and fill in the appropriate information as indicated.
If the vehicle is returned to continuous sea level (below 4,000 ft. alt.) operation, the Vehicle Emission Control Information Update Label should be removed and the above procedures should be reversed.
Parts Block
Warranty Status: Reimbursable within the provisions of the Warranty and Policy Manual.
Operation: SP 121 89-D-81
Time: 0.7 Hr.
DLR. Coding:
Basic Part No. Code:
DRIVE LO5