The 1990 GMC Sonoma Service and Repair Manual provides comprehensive, step-by-step instructions, diagrams, illustrations, wiring schematics, and specifications for maintaining, servicing, diagnosing, and repairing your 1990 GMC Sonoma. This manual covers all models and all repairs, from basic maintenance to complex technical issues. It offers the same detailed information used by technicians at dealerships, empowering you to handle repairs with confidence. The manual is organized into sections covering various vehicle systems, including: * **Engine:** Covers engine components, maintenance, troubleshooting, and repair procedures. * **Control System:** Includes information on electronic engine control systems, sensors, and actuators. * **Mechanical:** Addresses mechanical components such as the transmission, drivetrain, suspension, and brakes. * **Fuel Service Specifications:** Provides details on fuel system components, specifications, and troubleshooting. * **Emission Control:** Offers insights into emission control systems, components, and repair procedures. * **Intake Exhaust Cooling:** Covers intake and exhaust systems, cooling systems, and related components. * **Lube:** Provides information on lubrication systems, fluids, and maintenance intervals. * **Ignition Starting Charging:** Addresses ignition systems, starting systems, charging systems, and related components. * **Auto Transmission Clutch:** Includes information on automatic transmissions, clutches, and repair procedures. * **Manual Transmission:** Offers details on manual transmissions, components, and repair procedures. * **Transfer Propeller Shaft:** Covers transfer case, propeller shaft, and related components. * **Drive Shaft:** Addresses drive shaft components, maintenance, and repair procedures. * **Differential:** Provides information on differential systems, components, and repair procedures. * **Axle Suspension:** Includes details on axle and suspension systems, components, and repair procedures. * **Tire & Wheel:** Covers tire and wheel specifications, maintenance, and repair procedures. * **Brake Control:** Addresses brake control systems, components, and troubleshooting. * **Brake:** Includes information on brake systems, components, and repair procedures. * **Parking Brake:** Offers details on parking brake systems, components, and repair procedures. * **Steering Column:** Covers steering column components, maintenance, and repair procedures. * **Power Steering:** Addresses power steering systems, components, and repair procedures. * **Air Condition:** Includes information on air conditioning systems, components, and repair procedures. * **Suppl Restraint System:** Covers supplemental restraint systems, components, and repair procedures. * **Seat Belt:** Addresses seat belt systems, components, and repair procedures. * **Engine Immobilizer:** Includes information on engine immobilizer systems, components, and repair procedures. * **Cruise Control:** Covers cruise control systems, components, and repair procedures. * **Wiper & Washer:** Addresses wiper and washer systems, components, and repair procedures. * **Door Lock:** Includes information on door lock systems, components, and repair procedures. * **Meter Audio/Visual:** Covers meter and audio/visual systems, components, and repair procedures. * **Horn:** Addresses horn systems, components, and repair procedures. * **Windshield/Glass Mirror:** Includes information on windshield, glass, and mirror systems, components, and repair procedures. * **Instrument Panel:** Covers instrument panel components, maintenance, and repair procedures. * **Seat:** Addresses seat components, maintenance, and repair procedures. * **Engine Hood/ Door:** Includes information on engine hood and door components, maintenance, and repair procedures. * **Exterior & Interior:** Covers exterior and interior features, components, and repair procedures. * **Electrical:** Provides a comprehensive overview of electrical systems, circuits, and components. * **Multiplex/ Can Communication:** Addresses multiplex and CAN communication systems, components, and repair procedures. This manual provides comprehensive and detailed information for all aspects of your 1990 GMC Sonoma, allowing you to perform maintenance and repairs confidently and efficiently.

The 1990 GMC Sonoma is a compact pickup truck that was produced by General Motors from 1982 to 2004. The Sonoma was part of the Chevrolet S-10/GMC Sonoma platform, which was one of the most popular compact pickup truck platforms in the United States. The 1990 model year saw several significant updates to the Sonoma, including a new grille design, revised headlights and taillights, and a new interior. This year also brought the introduction of a new 4.3L V6 engine option, which was more powerful and fuel-efficient than the previous 2.8L V6. The 1990 Sonoma was offered in a variety of trim levels, including the base Sonoma, the SL, and the more luxurious Rally. The Sonoma came standard with rear-wheel drive, while four-wheel drive was available as an option. The 1990 GMC Sonoma's versatility and practicality made it popular among consumers. It was particularly well-suited for those who needed a vehicle that could handle light-duty hauling and towing tasks. Its compact size also made it easy to maneuver in tight spaces and park in urban environments. The Sonoma was known for its rugged construction, reliable powertrains, and relatively low cost of ownership. However, the 1990 Sonoma was not without its drawbacks. Its interior was somewhat spartan and lacked some of the creature comforts found in competing models. The suspension was also known to be somewhat harsh, particularly on rough roads. Nonetheless, the 1990 GMC Sonoma remained a popular choice for buyers seeking an affordable and capable compact pickup truck.