1991 GMC Light Duty Truck Fuel and Emissions Service Shop Repair Manual. Including Driveability. Fuel Injected (FI) Gasoline Engines Only. Original.

This service manual replaces Sections 6C and 6E for 2.5L, 2.8L, 4.3L, 5.0L, 5.7L, and 7.4L gasoline engines with throttle body injection and supplements the following shop manuals (NONE are Included):

X-9132 10-30 Series R-V-P Light Duty Truck Service Manual
X-9129 10 Series S-T Light Duty Truck Service Manual
X-9130 10 Series M-Van Light Duty Truck Service Manual
X-9131 10-30 Series C-K Light Duty Truck Service Manual
X-9157 10-30 Series G Light Duty Truck Service Manual

This manual includes the general description of a system, diagnosis and on-vehicle service procedures for the fuel control and emissions systems used on light duty trucks with a throttle body injection fuel control system.

Wiring diagrams for the above vehicles are published in separate Truck Wiring Diagram booklet (NOT Included).

Contents:
General Information
Driveability Symptoms
Computer Command Control
Fuel Control
Evaporative Emissions Control
Ignition System/EST
Electronic Spark Control
Air Management
Exhaust Gas Recirculation
Automatic Transmission Converter Clutch and Manual Transmission Shift Light
Positive Crankcase Ventilation
Thermostatic Air Cleaner
Special Tools and Specifications
Abbreviations
Alphabetical Index

Note: Service manuals can be valuable tools when working on and/or restoring a vehicle. For the uninitiated, keep in mind that these manuals were never meant as restoration manuals, as that is not within the regular scope of work done by dealership service departments (even today).

Condition: Service Manuals are used in Dealership Shops, Independent Garages and in Fleet Environments and thus can reflect such use, most often showing extensive signs of soiling, age, and wear. The information within is still legible and can give valuable insight. The images shown are representative of what is shipped.