W 250 Pickup V8-318 5.2L (1986)
Technical Service Bulletin # 250386
Date: 861103
High Altitude Conversion Packages
Models
1986 Light Duty Federal & California Trucks
Subject
High Altitude Conversion Packages & Adjustments for Improved Engine Performance
Index
EMISSIONS
Date
November 3, 1986
No.
25-03-86
P-3896
Packages are now available to accommodate a customer who may wish to convert a 1986 low altitude vehicle for improved high altitude (over 4,000 feet
above sea level) 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 package is voluntary and at the customer's expense.
The high altitude field conversion packages and procedures outlined below have been authorized on the following 1986 non-altitude equipped engine
families in service at altitudes above 4,000 feet above sea level.
Conversion Instructions
FIGURE 1
Sea Level to Altitude
IMPORTANT:
IN SOME OF THE CONVERSION PROCEDURES YOU WILL BE REQUIRED TO INSTALL A NEW VEHICLE
EMISSION CONTROL INFORMATION UPDATE LABEL PN 4275084.
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, then just
type in the new specification after the subject operation. 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."
In every case where this label is used, type in after - AUTHORITY OF - Technical Service Bulletin #25-03-86, and your dealer code below. Label PN