Generation:
First Generation (JDM: Sigma, Export: Diamante)
Production Years Covered By Manual:
1991, 1992, 1993, 1994, 1995, 1996
Chassis Codes:
F11A, F12A, F13A, F15A, F17A, F25A, F27A, F31A, F36A (varies by engine and drivetrain)
Segment:
Large/Mid-size Luxury Sedan and Wagon
Target Audience:
Individuals seeking comfortable, stylish, and technologically advanced transportation, often compared to domestic and European luxury offerings.
Key Competitors Early 90S:
Buick LeSabre/Park Avenue, Ford Taurus/Mercury Sable, Chevrolet Lumina, Oldsmobile Eighty-Eight/Lumina, Chrysler New Yorker, Toyota Camry, Honda Accord, Nissan Maxima, Volvo 240/740/940
Design Philosophy:
Emphasized European styling influences, spacious interior, quiet ride, and advanced features for its time.
Available Drivetrains:
Front-Wheel Drive (FWD) and All-Wheel Drive (AWD) with Mitsubishi's 'Super Select' system.
Engine Mechanical:
Engine overhaul, cylinder head, block assembly, lubrication system, cooling system, fuel system, emission control systems
Engine Electrical:
Ignition system, starting system, charging system, engine control system (ECU), fuel injection system
Transmission:
Automatic transmission (e.g., F4A51, V4A51), manual transmission (if applicable), clutch, transfer case (if AWD)
Drivetrain:
Front-wheel drive, All-wheel drive (Super Select 4WD), driveshafts, axles, differentials
Suspension:
Front suspension (e.g., MacPherson strut, multi-link), rear suspension (e.g., multi-link), steering system, wheel alignment
Brakes:
Front and rear brakes (disc, possibly drum for rear on some variants), ABS system, parking brake
Electrical Body:
Lighting system, power windows, power locks, mirrors, wipers, horn, body control modules
HVAC:
Heating, Ventilation, and Air Conditioning (HVAC) system components and service
Interior:
Trim removal and installation, seats, airbags (if equipped), dashboard
Exterior:
Body panels, bumpers, doors, hood, trunk, glass, seals
Diagnostics:
Troubleshooting guides, diagnostic trouble codes (DTCs), testing procedures for various systems
Maintenance:
Routine maintenance, fluid changes, filter replacements, tune-ups
Repair:
Detailed step-by-step repair procedures for all major components and systems
Disassembly Assembly:
Comprehensive instructions for component removal and reinstallation
Adjustments:
Calibration and adjustment procedures for various systems (e.g., brakes, clutch, suspension, engine timing)
Troubleshooting:
Systematic approaches to diagnose and resolve common and uncommon problems
Specifications:
Tightening torques, fluid capacities, wear limits, electrical specifications
Special Tools:
Identification and usage of special service tools required for specific procedures
Depth:
Comprehensive, bumper-to-bumper coverage suitable for professional mechanics and advanced DIYers
Diagrams Illustrations:
Pictorial diagrams, exploded views, schematics, and photos for clarity
Factory Specs:
Includes factory specifications, allowable limits, and reference data
Engine 1:
6G73 V6 SOHC 24-valve
Engine 1 Displacement:
2.5 Liters (2498 cc)
Engine 1 Bore X Stroke:
81.0 mm x 80.0 mm
Engine 1 Compression Ratio:
8.5:1 (approx.)
Engine 1 Horsepower:
160-170 hp @ 5500-6000 rpm (varies by market and year)
Engine 1 Torque:
176-180 lb-ft @ 3500-4500 rpm (varies by market and year)
Engine 2:
6G74 V6 SOHC 24-valve
Engine 2 Displacement:
3.0 Liters (2968 cc)
Engine 2 Bore X Stroke:
86.0 mm x 86.0 mm
Engine 2 Compression Ratio:
8.5:1 (approx.)
Engine 2 Horsepower:
195-210 hp @ 5500-6000 rpm (varies by market and year)
Engine 2 Torque:
200-215 lb-ft @ 3500-4500 rpm (varies by market and year)
Engine Management:
Electronic Fuel Injection (EFI) with engine control unit (ECU)
Fuel Type:
Unleaded gasoline (Octane rating may be specified in manual)
Fuel Delivery:
Multi-point fuel injection (MPI)
Fuel Pump:
Electric, in-tank
Length:
Approx. 4,965 mm (195.5 in) for sedan
Width:
Approx. 1,790 mm (70.5 in)
Height:
Approx. 1,425 mm (56.1 in) for sedan
Wheelbase:
Approx. 2,820 mm (111.0 in)
Curb Weight:
Approx. 1,550 - 1,750 kg (3,417 - 3,858 lbs) depending on configuration
Oil Change Interval:
Typically 3,000 - 5,000 miles (5,000 - 8,000 km) or 3-6 months, refer to manual for specific recommendations.
Timing Belt Replacement:
Crucial for V6 engines; typically 60,000 - 90,000 miles (96,000 - 145,000 km). Refer to manual for exact interval and procedure.
Coolant Change Interval:
Typically every 2-3 years or 30,000-50,000 miles (48,000-80,000 km).
Engine Oil Type:
API SG/SH or higher; SAE 10W-30 or 5W-30 depending on climate. Refer to manual for precise viscosity.
Engine Oil Capacity:
Approx. 4.5 - 5.0 liters (4.8 - 5.3 US quarts) with filter.
Coolant Type:
Ethylene glycol-based coolant (green or long-life pink/orange depending on original fill). Refer to manual for specification.
Brake Fluid Type:
DOT 3 or DOT 4.
Engine Issues:
Timing belt failure if not replaced on schedule, potential head gasket issues on higher mileage engines, intake manifold gasket leaks.
Transmission Issues:
Automatic transmission solenoids or clutch pack wear, occasional torque converter lock-up issues.
Suspension Issues:
Worn ball joints, tie rod ends, and control arm bushings due to age and mileage. Strut wear.
Electrical Issues:
Window regulators, power lock actuators, climate control module failures, corrosion on electrical connectors.
Brand:
Mitsubishi Motors, a Japanese automobile manufacturer known for innovation and diverse vehicle offerings.
First Generation Introduction:
Introduced in Japan in 1990 as the Mitsubishi Diamante/Sigma, later introduced to export markets like North America in 1991.
Design Influences:
Developed with significant input from Mitsubishi's European design studios, aiming for a sophisticated and European-inspired aesthetic.
Facelift:
A minor facelift occurred around 1994/1995 with updated styling, interior refinements, and potentially powertrain enhancements.
Production Locations:
Primarily produced in Japan.
