🏷️ Basic Information

Make:

Kia

Model:

Optima

Year:

2004

Chassis Code:

MS

👋 Introduction

Segment:

Mid-size Sedan

Competitors 2004:

Toyota Camry, Honda Accord, Nissan Altima, Ford Fusion, Chevrolet Malibu.

Value Proposition:

The Kia Optima (MS) offered competitive styling, a spacious interior, and a strong value proposition compared to its more established Japanese and American rivals, aiming to capture market share through affordability and features.

Powertrain Options:

Available with a fuel-efficient 2.4L inline-four or a more powerful 2.7L V6 engine, paired with either a manual or automatic transmission, providing options for different driving preferences and needs.

Styling:

Featured a European-influenced design aesthetic for its generation, contributing to a more sophisticated appearance than some of its predecessors.

📋 Manual Details

Engine Variants Covered:

2.4L Inline-4 (G4JS), 2.7L V6 (G6BA)

Transmission Variants Covered:

4-speed Automatic, 5-speed Manual

Trim Levels Covered:

All trims (e.g., LX, EX)

Estimated Page Count:

1000+

Type:

Service and Repair Workshop Manual

Language:

English

Format:

PDF Download

📖 Manual Coverage

Engine Mechanical:

Engine assembly, cylinder head, block, crankshaft, pistons, connecting rods, lubrication system, cooling system, timing belt/chain, valve train.

Fuel System:

Fuel tank, fuel pump, fuel injectors, fuel pressure regulator, fuel filter, evaporative emission control (EVAP).

Ignition System:

Ignition coils, spark plugs, crankshaft position sensor, camshaft position sensor.

Exhaust System:

Exhaust manifold, catalytic converter, muffler, oxygen sensors (O2 sensors).

Transmission Manual:

Clutch system, gearbox assembly, gears, synchronizers, shift mechanism.

Transmission Automatic:

Torque converter, valve body, planetary gear sets, hydraulic control system, transmission control module (TCM).

Drivetrain:

Front-wheel drive (FWD) components, axles, CV joints, differential.

Suspension:

Front suspension (struts, control arms, ball joints), rear suspension (multi-link or independent), springs, shock absorbers, sway bars.

Steering:

Power steering system (hydraulic pump, steering rack, hoses), steering column, tie rods.

Brakes:

Front and rear disc brakes, brake calipers, brake pads, brake rotors, master cylinder, brake booster, ABS (Anti-lock Braking System) components, parking brake.

Electrical System:

Battery, alternator, starter motor, wiring diagrams, fuses, relays, lighting system (headlights, taillights, interior lights), horn.

Body And Chassis:

Frame structure, body panels, doors, hood, trunk, glass, interior trim, bumpers.

Heating Ventilation Air Conditioning HVAC:

A/C compressor, condenser, evaporator, blower motor, climate control panel, refrigerant lines, heater core.

Driver Information System:

Instrument cluster, gauges, warning lights, trip computer.

Maintenance Tasks:

Oil and filter change, air filter replacement, cabin air filter replacement, spark plug replacement, coolant flush, brake fluid replacement, transmission fluid change, drive belt inspection/replacement.

Diagnostic Procedures:

Troubleshooting guides for common symptoms, diagnostic trouble codes (DTCs) interpretation, on-board diagnostics (OBD-II) information.

Repair Procedures:

Component removal and installation for all major systems, engine overhaul, transmission overhaul, brake caliper rebuild, suspension component replacement, electrical component repair.

Engine Repair:

Detailed steps for cylinder head gasket replacement, piston ring replacement, crankshaft seal replacement, timing belt/chain system service.

Transmission Repair:

Internal transmission component replacement, solenoid testing, valve body service, torque converter replacement.

Electrical Diagnostics:

Component testing, circuit diagnosis using wiring diagrams, troubleshooting electrical faults.

HVAC Service:

Refrigerant charging, leak detection, component replacement (compressor, evaporator), blower motor service.

Brake System Service:

Brake pad and rotor replacement, caliper service, bleeding the brake system, ABS system diagnostics.

Depth:

Comprehensive - covers basic maintenance to full engine and transmission rebuilds, including electrical diagnostics and troubleshooting.

Detail Level:

Includes torque specifications, tightening sequences, specific tool requirements, and step-by-step illustrated instructions.

📊 Manual Specifications

Type:

PDF

Searchability:

Searchable text content for quick information retrieval.

Quality:

High-resolution digital reproduction, suitable for printing individual pages or the entire manual.

Type:

N/A (Digital Download)

Type:

N/A (Digital Download)

⚙️ Engine Specifications

Engine 1 Type:

Inline-4

Engine 1 Displacement:

2.4 Liters (2351 cc)

Engine 1 Code:

G4JS

Engine 1 Bore X Stroke:

86.0 mm x 100.0 mm

Engine 1 Compression Ratio:

9.7:1

Engine 1 Horsepower:

144 hp @ 5500 rpm

Engine 1 Torque:

153 lb-ft @ 4000 rpm

Engine 2 Type:

V6

Engine 2 Displacement:

2.7 Liters (2656 cc)

Engine 2 Code:

G6BA

Engine 2 Bore X Stroke:

86.7 mm x 75.0 mm

Engine 2 Compression Ratio:

9.6:1

Engine 2 Horsepower:

170 hp @ 6000 rpm

Engine 2 Torque:

180 lb-ft @ 4000 rpm

Fuel Delivery:

Multi-port Fuel Injection (MPI)

Fuel Type:

Unleaded Gasoline

Fuel Tank Capacity:

14.4 gallons (54.5 Liters)

🔧 Transmission

Type:

5-speed Manual Transmission

Type:

4-speed Automatic Transmission

Automatic Features:

Electronically controlled, with lock-up torque converter.

Manual Gear Ratios:

Refer to manual for specific ratios by gear.

Automatic Gear Ratios:

Refer to manual for specific ratios by gear.

📐 Dimensions

Length:

187.4 inches (4760 mm)

Width:

70.1 inches (1780 mm)

Height:

57.3 inches (1455 mm)

Wheelbase:

106.3 inches (2700 mm)

Front Track:

60.4 inches (1535 mm)

Rear Track:

60.2 inches (1530 mm)

Ground Clearance:

Approx. 5.7 inches (145 mm)

Passenger Volume:

Approx. 98.5 cubic feet (2789 L)

Front Headroom:

Approx. 39.8 inches (1011 mm)

Rear Headroom:

Approx. 37.7 inches (958 mm)

Front Legroom:

Approx. 42.1 inches (1069 mm)

Rear Legroom:

Approx. 36.9 inches (937 mm)

Trunk Volume:

Approx. 14.7 cubic feet (416 L)

Curb Weight Min:

Approx. 3232 lbs (1466 kg) (2.4L Manual)

Curb Weight Max:

Approx. 3439 lbs (1560 kg) (2.7L Automatic)

Gross Vehicle Weight Rating Gvwr:

Refer to manual for specific GVWR

Wheel Bolt Pattern:

5 x 114.3 mm (5 x 4.5 inches)

Standard Tire Size:

P205/60R16

Optional Tire Size:

P215/55R17 (on EX trims)

🛡️ Safety Features

NHTSA Frontal Driver Rating:

Four Stars

NHTSA Frontal Passenger Rating:

Four Stars

NHTSA Side Driver Rating:

Four Stars

NHTSA Side Rear Passenger Rating:

Four Stars

NHTSA Rollover Rating:

Four Stars

ABS:

Standard (4-wheel disc brakes on most models)

Traction Control:

Optional on some trims

Electronic Stability Control Esc:

Not widely available/standard for this model year.

Airbags Front:

Driver and front passenger airbags

Airbags Side:

Front side-impact airbags

Airbags Curtain:

Available on some higher trims

Seatbelts:

Three-point seatbelts with pretensioners for all occupants.

Child Seat Anchors:

LATCH (Lower Anchors and Tethers for CHildren) system

💡 Technology Features

Audio System:

Standard AM/FM stereo with CD player. Optional premium sound systems may have been available on higher trims, potentially including a cassette player and more speakers.

Navigation:

No integrated navigation system was standard or commonly available for this model year. Aftermarket options were prevalent.

Cruise Control:

Standard on most trims.

Keyless Entry:

Available on some trims.

Bluetooth:

Not available as a factory option for this model year.

🔧 Maintenance

Oil And Filter Change:

Every 5,000 miles (8,000 km) or 6 months, whichever comes first.

Air Filter Replacement:

Every 15,000 miles (24,000 km) or 12 months.

Cabin Air Filter Replacement:

Every 15,000 miles (24,000 km) or 12 months.

Spark Plug Replacement 4Cyl:

Every 60,000 miles (96,000 km) with iridium plugs, or 30,000 miles (48,000 km) with standard plugs.

Spark Plug Replacement V6:

Every 60,000 miles (96,000 km) with iridium plugs, or 30,000 miles (48,000 km) with standard plugs.

Coolant Flush:

Every 30,000 miles (48,000 km) or 24 months.

Brake Fluid Replacement:

Every 30,000 miles (48,000 km) or 24 months.

Transmission Fluid Change Auto:

Every 60,000 miles (96,000 km)

Transmission Fluid Change Manual:

Every 60,000 miles (96,000 km)

Timing Belt Replacement:

Every 90,000 miles (144,000 km) or 7 years (for the 2.4L engine). The 2.7L V6 uses a timing chain, which is typically maintenance-free unless issues arise.

Engine Oil Type 4Cyl:

API SL or higher, SAE 5W-30 or 5W-40. Consult manual for specific viscosity based on temperature range.

Engine Oil Type V6:

API SL or higher, SAE 5W-30 or 5W-40. Consult manual for specific viscosity based on temperature range.

Engine Oil Capacity 4Cyl:

Approx. 4.2 US quarts (4.0 L) with filter change.

Engine Oil Capacity V6:

Approx. 4.5 US quarts (4.3 L) with filter change.

Coolant Type:

Ethylene Glycol based coolant (Green) conforming to ASTM D3306.

Coolant Capacity:

Approx. 6.4 US quarts (6.1 L) for 4-cyl, 7.3 US quarts (6.9 L) for V6.

Automatic Transmission Fluid Type:

Kia Genuine ATF SP-III or equivalent.

Manual Transmission Fluid Type:

API GL-4, SAE 75W-90 gear oil.

Power Steering Fluid Type:

Kia Genuine Power Steering Fluid or Dexron III ATF.

Brake Fluid Type:

DOT 3 brake fluid.

Engine Performance:

Some reports of oil leaks from valve cover gaskets or crankshaft seals. Occasional issues with engine mounts causing vibrations.

Transmission Issues:

The automatic transmission can sometimes exhibit delayed shifting or rough engagement. Regular fluid changes are crucial. Some manual transmissions may develop clutch wear.

Suspension And Steering:

Worn front suspension components (ball joints, tie rod ends) and power steering rack leaks can occur over time.

Electrical Component Failures:

Alternator failures and issues with power window regulators have been noted.

HVAC System:

A/C system compressor failures or refrigerant leaks can be problematic.

📚 Vehicle History

Kia History:

Kia Motors Corporation, founded in 1944, is South Korea's oldest manufacturer of motor vehicles. It has grown from a producer of bicycle parts and motorcycles to a global automotive powerhouse known for its value, design, and increasingly, its technological advancements.

Optima Generation 1:

The 2004 Optima (MS) is part of the first generation of the Optima, which was introduced in 2000. It was marketed as the Kia Optima or Kia Magentis in many international markets. This generation was based on the Hyundai Sonata platform.

Optima Redesign 2004:

The 2004 model year received a significant facelift, including updated exterior styling (new grille, headlights, taillights, and bumpers), interior enhancements, and revised suspension tuning, aimed at improving its competitive standing.

Manufacturing Locations:

Primarily produced in South Korea, with potential assembly in other regions for specific markets.

🏆 Awards & Recognition

Safety Awards:

As noted in safety ratings, achieved favorable 4-star ratings from NHTSA in frontal and side impact tests for its year.

Value Awards:

While specific major awards are not prominent for this model year, the Optima consistently aimed to offer competitive pricing and feature sets in the mid-size sedan market.

Emissions Certification:

Compliant with U.S. EPA and California ARB emissions standards applicable for the 2004 model year.