Primary Coverage:
Comprehensive service and repair for the 1990 Audi 100 (C4-4A).
Model Variants Covered:
All models and configurations of the 1990 Audi 100 (C4-4A) including sedan and Avant variants.
Estimated Page Count:
1000+
Type:
Service and Repair Manual
Purpose:
Designed for professional technicians and experienced DIY enthusiasts.
Content Focus:
Technical service data, repair instructions, diagnostic procedures, specifications, and torque values.
Engine Systems:
Engine mechanical (block, head, pistons, crankshaft, camshafts), fuel injection (CIS-E, KE-Jetronic), ignition, cooling, lubrication, exhaust, emissions control.
Transmission Systems:
Manual and automatic transmission overhaul, clutch, driveline, CV joints, differentials.
Chassis And Suspension:
Front and rear suspension, steering system, wheel bearings, shock absorbers, springs, bushings.
Brake Systems:
Hydraulic brake system, ABS (Anti-lock Braking System), brake pads, rotors, calipers, lines, master cylinder.
Electrical Systems:
Wiring diagrams, starter, alternator, battery, lighting, instruments, dashboard controls, fuses, relays, onboard diagnostics (OBD).
Body And Interior:
Body panels, doors, locks, hinges, glass, upholstery, climate control, HVAC, seat adjustments.
Cooling System:
Radiator, water pump, thermostat, heater core, fan operation, coolant flush procedures.
Lubrication System:
Oil pump, oil filter housing, oil pan, oil cooler (if equipped).
Ignition System:
Distributor, ignition coil, spark plug wires, spark plugs, ignition control module (ECU).
Maintenance Procedures:
Routine maintenance checks, oil changes, filter replacements, fluid level checks, belt inspections and replacement, spark plug replacement.
Repair Procedures:
Engine rebuilds, transmission repairs, suspension component replacement, brake service, electrical component diagnosis and repair, body panel repair.
Troubleshooting Diagnostics:
Systematic diagnostic procedures, fault code interpretation, symptom-based troubleshooting for all major vehicle systems.
Bodywork Repair:
Panel alignment, rust repair techniques, body trim removal and installation, window sealing.
Diagnostic Charts:
Detailed fault-finding charts correlating symptoms to potential causes and diagnostic steps.
Depth:
In-depth, dealership-level technical information covering complete overhauls, complex diagnostics, and specialized repair procedures.
Engine Code Common:
Various, including 5-cylinder variants (e.g., 2.3L, 2.2L Turbo).
Engine Displacement Example:
2.3 Liters (2309 cc)
Engine Configuration Example:
Inline 5-cylinder, SOHC or DOHC
Horsepower Example:
~130 hp @ 5500 rpm (2.3E)
Torque Example:
~137 lb-ft @ 3000 rpm (2.3E)
Fuel Delivery:
Bosch CIS-E (Continuous Injection System - Electronic) or KE-Jetronic fuel injection.
Fuel Type:
Unleaded Gasoline
Oil Change Interval Example:
Every 10,000 km (6,000 miles) or 12 months, whichever comes first.
Timing Belt Replacement Example:
Every 80,000 - 100,000 km (50,000 - 60,000 miles) or 5 years.
Engine Oil Type Example:
API SG or higher, SAE 5W-40 or 10W-40 depending on climate.
Coolant Type Example:
G11 (Blue-Green) ethylene glycol coolant.
Brake Fluid Type:
DOT 3 or DOT 4.
Automatic Transmission Fluid Example:
G 052 162 A1 or equivalent ATF (e.g., Dexron II).
Common Electrical Problems:
Corrosion in wiring harnesses, faulty door lock actuators, headlight switch failure.
Common Engine Problems:
Degradation of vacuum lines, distributor cap/rotor wear, idle control valve issues, oil leaks from seals.
Common Suspension Problems:
Worn ball joints, control arm bushings, and strut mounts.
Common Fuel System Problems:
Warm-up regulator (WUR) issues with CIS-E systems, fuel accumulator failure.
