Conversion of Low Altitude System to High Altitude

Dealers in high altitude areas should encourage owners who have moved to high altitude counties to purchase the following adjustment procedure. This adjustment is considered an owner maintenance expense. See attachment for a list of counties which the Environmental Protection Agency has designated as high altitude counties. Diesel timing should be checked or adjusted at the same approximate altitude at which the vehicle will be driven.

FIGURE 1:

1. Replace the EGR vacuum control valve assembly with EGR vacuum control valve assembly part number 22519396 or equivalent. Refer to Figure 1.
2. Remove and discard the vacuum modulator valve, if so equipped, as shown in Figure 1.

FIGURE 2:

3. Reroute the vacuum hoses as indicated in Figure 2.

4. Install Timing Meter J-33075 or equivalent, set pump timing to -6~, and set idle speed to specifications. Turn off engine.
5. Remove air crossover assembly. Install screen covers J-29657.
6. With transmission in Park and A/C off, start engine.

FIGURE 3:

7. Loosen locknut (Figure and slowly turn metering valve stop screw clockwise until idle speed drops approximately 10 RPM.

8. Turn metering valve stop screw counterclockwise 2-1/8 turns. Tighten locknut.
9. Check for fuel leaks around metering valve stop screw.
10. Turn engine off.
11. Remove magnetic tachometer probe and screened covers from intake manifold and reinstall air crossover and air cleaner.

FIGURE 4:

12. Fill in dealer code and date on the supplemental emission control label, part number 14057201 or equivalent (Figure 4). This label must be placed next to the existing underhood emission control information label. Wash off the area with soap and water, dry thoroughly, and apply the new label.

PARTS INFORMATION

Part Part Number

1. EGR Vacuum Control Valve Assembly 22519396 or equivalent High Altitude Application
2. Label 14057201 or equivalent

Suggested Time

The suggested time to perform the high Altitude Adjustment and part replacement is 0.8 hour labor.
Dealers in high altitude areas should encourage owners who have moved to high altitude counties to purchase the following adjustment procedure. This adjustment is considered an owner maintenance expense. See attachment for a list of counties which the Environmental Protection Agency has designated as high altitude counties. Diesel timing should be checked or adjusted at the same approximate altitude at which the vehicle will be driven.

FIGURE 6:

1. Replace the EGR vacuum control valve assembly with the assembly shown in Figure 6. Refer to Parts Information for part numbers.
2. Install Timing Meter J-33075 or equivalent, set pump Timing to -6~, and set engine idle to specifications, turn off engine.
3. Remove air crossover assembly. Install screen covers J-29657
4. With transmission in Park and A/C off, start engine.

FIGURE 7:

5. Loosen locknut (Figure 7) and slowly turn metering valve stop screw clockwise until idle speed drops approximately 10 RPM.
6. Turn metering valve stop screw counterclockwise exactly 2-1/8 turns. Tighten locknut.

7. Check for fuel leaks around metering valve stop screw.
8. Turn engine off.
9. Remove magnetic tachometer probe and screened covers from intake manifold and reinstall parts removed.

FIGURE 5:

10. Fill in dealer code and date on the supplemental emission control label, part number 14057201 or equivalent (Figure 5). This label must be placed next to the existing underhood emission control information label. Wash off the area with soap and water, dry thoroughly, and apply the new label.
PARTS INFORMATION

Part Part Number
1. EGR Vacuum Control Valve Assembly 22519396 or equivalent High Altitude Application
2. Label 14057201 or equivalent
Suggested Time

The suggested time to perform the Low to High Altitude Adjustment and part replacement of 0.8 hour labor
Dealers in high altitude areas should encourage owners who have moved to high altitude counties to purchase the service adjustment procedure outlined below, which is considered an owner maintenance expense. See attachment for a list of counties which the Environmental Protection Agency has designated as high altitude counties. Diesel timing should be checked or adjusted at the same approximate altitude at which the vehicle will be driven.

FIGURE 8:

1. Replace the EGR vacuum control valve assembly (Figure 8) with the assembly shown in the parts information.
2. Install timing meter J-33075 or equivalent, set pump timing -4~, and set idle speed to specifications.
3. Remove air cleaner and air crossover assemblies and install screen covers J-26996-2.

FIGURE 9:

4. Install shop towel in the intake manifold valley area under the injection pump head to absorb any full leakage. Remove housing pressure tap plug and seal located on the rear of the pump (Figure 2).
5. Using the parts contained in kit, part number 22516487 or equivalent, assemble locknut and new seal (O-ring) to metering valve stop screw.
6. Install assembly in injection pump until locknut contacts pump housing. Tighten locknut.
7. Place transmission in Park, turn A/C off and start engine.
8. Loosen locknut and slowly turn metering valve stop screw clockwise until idle speed drops approximately 10 RPM.
9. Turn metering valve stop screw counterclockwise 2-1/2 turns and tighten locknut.
10. Check installation for fuel leaks and remove shop towel from intake valley.
11. Turn engine off.
12. Remove timing meter and screened covers from intake manifold and reinstall parts removed.

FIGURE 5:

13. Type or print with ball point pen the dealer code and date in the space provided on the supplemental emission control label, part number 14057201 or equivalent, Figure 5 (part of kit). The label must be placed next to the existing underhood emission control information label to the extent possible. The label should not be affixed to any equipment that can be easily detached from the vehicle. Wash off the area with soap and water, dry thoroughly, and apply the new label.
PARTS INFORMATION

Part Part Number
1. EGR Vacuum Control Valve Assembly 22515542 or equivalent High Altitude Application-All Models
2. Kit Contents 22516487 or equivalent