Segment:
Compact Car / Hatchback
Target Audience:
DIY enthusiasts, independent repair shops, and owners seeking detailed maintenance and repair information.
Key Competitors:
Honda Civic, Toyota Corolla, Ford Focus, Mazda3
Design:
Solid build quality, refined interior, practical hatchback design.
Powertrains:
Known for reliable and fuel-efficient engines, particularly the 1.8T.
Handling:
Good balance of ride comfort and sporty handling, especially in GTI variants.
Engine:
1.8L Turbo (AGU/AWP), 2.0L naturally aspirated (APK/AZG/AVH/BBW), 2.8L VR6 (AGM/AAA - less common for 2002 NA models, focus on 1.8T/2.0L)
Engine Management:
ECU diagnostics, fuel injection, ignition system, emissions control
Transmission Manual:
5-speed (02J), 6-speed (02M - for 1.8T)
Transmission Automatic:
4-speed automatic (01M, 01N)
Drivetrain:
Front-Wheel Drive (FWD), Haldex All-Wheel Drive (4MOTION - less common for base 2002 models, but applicable for GTI/GLI)
Suspension:
Front McPherson strut, rear independent torsion beam (or multi-link for 4MOTION)
Brakes:
Front ventilated discs, rear solid discs (or drums on base models), ABS system
Steering:
Hydraulic power steering, steering rack
Electrical:
12V system, battery, alternator, starter, lighting, body control module (BCM), fuse box diagrams
HVAC:
Heating, Ventilation, Air Conditioning (including refrigerant R134a)
Body:
Exterior panels, doors, windows, interior trim, body repairs
Body Electrical:
Wiper system, power windows, central locking, power mirrors
Safety Systems:
Airbag system (SRS), seatbelt pre-tensioners
Routine Maintenance:
Oil changes, filter replacements, spark plugs, fluid checks, belt inspections
Major Repairs:
Engine component removal and installation (e.g., alternator, starter, water pump), clutch replacement
Engine Overhaul:
Cylinder head removal/installation, piston and connecting rod service, crankshaft service
Transmission Service:
Clutch hydraulic system, transmission fluid changes, manual transmission internal inspection/repair, automatic transmission component replacement
Brake Service:
Brake pad and rotor replacement, brake caliper service, bleeding procedure, ABS sensor replacement
Suspension Repair:
Strut and shock absorber replacement, control arm bushing replacement, ball joint service
Electrical Troubleshooting:
Wiring diagrams, component testing, diagnostic trouble codes (DTCs) and procedures
HVAC Service:
Component replacement (compressor, condenser, evaporator), refrigerant system evacuation and recharge, leak detection
Body Repair:
Door panel removal, window regulator repair, mirror replacement, minor body panel alignment
Diagnostic Procedures:
Step-by-step guides for diagnosing common and uncommon faults across all systems.
Depth:
Comprehensive, from basic maintenance to complete engine and transmission rebuilds, including electrical diagnostics.
Diagnostic Tools:
Information on using OBD-II scanners and specific VW diagnostic tools (e.g., VAG-COM)
Engine 1.8T:
1.8L DOHC 20-valve turbocharged inline-4 (AGU/AWP)
Engine 2.0L:
2.0L SOHC 8-valve naturally aspirated inline-4 (APK/AZG/AVH/BBW)
1.8T Horsepower:
150 hp @ 5700 rpm (approx.)
1.8T Torque:
162 lb-ft @ 1750 rpm (approx.)
2.0L Horsepower:
115 hp @ 5200 rpm (approx.)
2.0L Torque:
122 lb-ft @ 3200 rpm (approx.)
Injection Type:
Multi-point fuel injection (MPI) or Electronic Fuel Injection (EFI)
Fuel Type:
Unleaded gasoline (91 octane or higher recommended for 1.8T)
Manual Transmission:
5-speed manual (02J) for 2.0L, 6-speed manual (02M) for 1.8T
Automatic Transmission:
4-speed automatic (01M, 01N)
Clutch:
Hydraulically actuated single dry plate clutch
Transmission Fluid Manual:
VW G 052 171 A2 (or equivalent GL-4 75W-90)
Transmission Fluid Automatic:
VW G 052 162 A2 (or equivalent ATF type)
Oil Change Interval:
Every 5,000 - 7,500 miles or 12 months (whichever comes first), depending on driving conditions and oil used.
Timing Belt Replacement:
100,000 miles or 10 years for 1.8T (and some 2.0L engines with interference design), check manual for specific engine code. **Critical:** Failure to replace can cause catastrophic engine damage.
Coolant Flush:
Every 30,000 miles or 2 years.
Engine Oil:
SAE 5W-40 or 5W-30, meeting VW 502.00/505.00 specifications (synthetic recommended).
Coolant:
G12 (pink) or G12+ antifreeze (Volkswagen Genuine Coolant).
Ignition Coils:
Coil-on-plug ignition coils are prone to failure, causing misfires. Often replaced as a set.
Mass Air Flow Sensor:
Can become dirty or fail, leading to poor idling and performance issues.
Window Regulators:
Plastic components within the regulator mechanism can break, causing power windows to fail.
Rear Main Seal:
Can leak oil over time, requiring transmission removal for replacement.
ABSorbent Glass Mat Battery:
Early Mk4 models may have used conventional batteries; later ones often came with AGM types. Ensure correct replacement type.