🏷️ Basic Information

Make:

Buick

Model:

Regal

Year:

1991

Generation Code:

LN3/L27 (Third Generation)

Platform:

GM W-body

👋 Introduction

Segment:

Mid-size personal luxury coupe/sedan

Key Competitors:

Ford Thunderbird, Chevrolet Lumina, Oldsmobile Cutlass Supreme, Pontiac Grand Prix.

Unique Selling Points:

The 1991 Regal offered a comfortable ride, stylish (for its era) styling, and optional performance engines, positioning itself as a more upscale option in the W-body platform.

📋 Manual Details

Systems Covered:

Engine, Fuel Service, Emission Control, Intake/Exhaust/Cooling, Lube, Ignition, Starting/Charging, Automatic Transmission, Manual Transmission, Transfer/Propeller Shaft, Drive Shaft, Differential, Axle/Suspension, Tire/Wheel, Brake Control, Brake, Parking Brake, Steering Column, Power Steering, Air Conditioning, Supplemental Restraint System (SRS), Seat Belt, Engine Immobilizer, Cruise Control, Wiper/Washer, Door Lock, Meter/Audio/Visual, Horn, Windshield/Glass/Mirror, Instrument Panel, Seat, Engine Hood/Door, Exterior/Interior, Electrical, Multiplex/CAN Communication, Diagnostics, Troubleshooting, Maintenance, Repair Procedures

Estimated Page Count:

High (Detailed Factory Manual Equivalent, typically 1000+ pages for comprehensive coverage)

Type:

Service and Repair Manual

Language:

English

Format:

PDF Download

📖 Manual Coverage

Engine Systems:

Detailed coverage of 3.1L V6 (LN3) and 3.8L V6 (L27) engines, including mechanical, fuel injection, ignition, cooling, lubrication, emission controls, and diagnostics.

Drivetrain Systems:

Comprehensive information on automatic transmissions (e.g., 4T60/4T60-E), manual transmissions (less common for this model year but if equipped), drive axles, differentials, suspension components, and steering systems.

Electrical Systems:

In-depth coverage of the entire electrical system, including wiring schematics for all circuits, lighting, instrumentation, audio systems, power accessories, cruise control, and the supplemental restraint system (SRS).

Maintenance Procedures:

Routine maintenance tasks such as oil changes, filter replacements, fluid checks and changes, spark plug replacement, belt inspection and replacement, and tune-up procedures.

Diagnostic Procedures:

Step-by-step diagnostic routines for identifying and troubleshooting common and complex problems across all vehicle systems, including fault code interpretation (OBD-I).

Repair Procedures:

Detailed, A-Z repair instructions for virtually every component and system, from minor adjustments to major component overhauls and replacements. Includes disassembly, assembly, and torque specifications.

Depth Of Information:

Factory-level technical detail, equivalent to what dealership technicians use. Covers diagnostics, specifications, repair procedures, and component testing.

📊 Manual Specifications

Format Details:

PDF, compatible with Windows (Vista32/64, XP, ME, 98, NT, 2000) and Mac operating systems.

Printability:

Fully printable. Allows users to print specific pages or entire sections for use in the workshop. Images can be enlarged for better viewing.

Binding:

Not Applicable (Digital PDF format)

Paper Quality:

Not Applicable (Digital PDF format). However, print quality depends on the user's printer.

⚙️ Engine Specifications

Engine Options:

3.1L (189 ci) V6 (LN3), 3.8L (231 ci) V6 (L27 - naturally aspirated and potentially supercharged '3800' in some variants, though less common in 1991 Regal)

Horsepower Torque 3.1L:

Approx. 140 hp @ 4400 rpm / 180 lb-ft @ 3200 rpm (LN3)

Horsepower Torque 3.8L:

Approx. 165 hp @ 4000 rpm / 210 lb-ft @ 2400 rpm (L27)

Fuel Delivery:

Multi-port Fuel Injection (MPFI)

🔧 Transmission

Transmission Type Standard:

4-speed automatic (e.g., 4T60)

Transmission Type Optional:

Possibly 4T60-E (electronically controlled automatic) depending on trim and specific build

Transmission Features:

Overdrive, torque converter lock-up for improved fuel efficiency.

📐 Dimensions

Wheelbase:

Approx. 107.5 inches

Length:

Approx. 195.7 inches

Width:

Approx. 70.5 inches

Height:

Approx. 54.3 inches

Curb Weight:

Approx. 3200-3400 lbs (varies by body style and options)

🛡️ Safety Features

NHTSA Ratings:

As specific NHTSA crash test data for 1991 models is less readily available in digital format, refer to the manual for detailed safety system information. Generally, this era of GM vehicles had front and some side-impact protection.

Active Safety Features:

Anti-lock Braking System (ABS) often optional.

Passive Safety Features:

Seat belts (manual adjustment), Supplemental Restraint System (SRS) - driver's side airbag became more common in this era, check specific model features.

💡 Technology Features

Audio System:

Factory AM/FM stereo with cassette player. Optional premium sound systems and CD players were available.

Driver Assistance Features:

Cruise control was a common feature. Anti-lock brakes (ABS) were often an option.

Connectivity Options:

Limited by 1991 standards. No integrated Bluetooth or USB. Some models may have had basic cellular phone integration (external).

🔧 Maintenance

Oil Change Interval:

Typically every 3,000-5,000 miles or 3-6 months, depending on driving conditions and oil type (refer to manual for specific recommendations).

Transmission Fluid Change:

Check manual, but generally around 30,000-60,000 miles for automatic transmissions.

Engine Oil Type:

Consult manual for viscosity (e.g., 5W-30 or 10W-30) and API service classification. Dexos is a modern standard not applicable here; look for GM 6094M or similar.

Transmission Fluid Type:

Dexron-III (or compatible equivalent) for 4T60/4T60-E transmissions.

Common Wear Items:

Suspension components (bushings, ball joints), exhaust system, fuel injectors, intake manifold gaskets (3.1L), transmission solenoid issues. Electrical connectors can be prone to corrosion.

Engine Specific Notes 3.1L:

The 3.1L V6 (LN3) can be prone to intake manifold gasket leaks and occasional issues with the distributor-less ignition system.

Engine Specific Notes 3.8L:

The 3.8L V6 (L27) is generally robust. Early models with specific issues related to intake manifold gaskets or cooling systems should be noted, though less prevalent than on some later iterations.

📚 Vehicle History

Buick Legacy:

Buick has a long history of producing comfortable, well-appointed, and often powerful personal luxury vehicles, a tradition the Regal carried forward.

Regal Third Generation:

The third generation (1988-1996) introduced the W-body platform, offering a more modern, sleeker design and improved performance compared to its predecessors. The 1991 model year brought refinements and potential updates to engine management and features.

Manufacturing Location:

General Motors assembly plants in North America (e.g., Lansing, Michigan).

🏆 Awards & Recognition

Model Awards:

The Regal was often recognized for its comfortable ride and quiet interior, typical of Buick's positioning. Specific awards for the 1991 model year are not prominently documented as major accolades but it was a strong seller in its segment.