B350 1 Ton Van V8-360 5.9L VIN W 4-bbl (1988)
Air/Fuel Mixture: Technical Service Bulletins
Engine - High Altitude Conversion & Adjustment
No.
P-4243
25-05-88
Date
October 10, 1988
Index
EMISSIONS
Subject
High Altitude Conversions and Adjustments for Improved Engine Performance at Altitude (4000 Feet and Above)
Models
1988 B-D-N-W-AD- & AW-Trucks
Instructions are now available to accommodate a customer who may wish to convert a 1988 low-altitude vehicle for improved high-altitude engine
performance.
Vehicles with the low-altitude package transferred to service in high-altitude areas may exhibit undesirable driveability. However, the installation of a
high-altitude conversion is voluntary and at the customer's expense.
The high-altitude field conversion packages and procedures outlined below have been authorized on the following 1988 nonaltitude-equipped engine
families in service at altitudes 4,000 feet above sea level.
CONVERSION INSTRUCTIONS
Sea Level to Altitude
IMPORTANT:
IN ALL OF THE CONVERSION PROCEDURES YOU WILL BE REQUIRED TO INSTALL A NEW VEHICLE EMISSION CONTROL
INFORMATION UPDATE LABEL, PN 4375084.
THIS LABEL HAS TWO AREAS THAT ARE IMPACT IMPRINTABLE WITH A TYPEWRITER (SEE FIGURE 1.)
If you are required to readjust timing, curb idle speed, or fast idle speed to a specification different than the original VECI label specification, type in the
new specification. If you are asked to refer to the original VECI label specifications, type in on the right hand side of the label "refer to original VECI
label."
Type in Technical Service Bulletin 25-05-88 and your dealer code as shown in Figure 1. Label, PN 4275084, is available from the parts supply.
The following chart should be used to identify what parts must be used on what package.
