Audi, A6, C4, 1.8 5v Quattro (1995-) Common Issues
1. Rust on bodywork
Occurrence: 25%Cost to repair: $800Symptoms:
Visible rust spots, particularly on door sills and lower panels.
2. Faulty oxygen sensor
Occurrence: 18%Cost to repair: $300Symptoms:
Check Engine light comes on, engine may stumble or hesitate.
3. Faulty Mass Airflow Sensor (MAF)
Occurrence: 15%Cost to repair: $250Symptoms:
Engine may stutter, stumble or not run at all.
4. CV Joint Failure
Occurrence: 12%Cost to repair: $600Symptoms:
Clunking or grinding noise from the front wheels when driving over bumps.
5. Faulty Alternator Belt
Occurrence: 10%Cost to repair: $200Symptoms:
Engine may stall, battery warning light on dashboard.
6. Coolant leak
Occurrence: 9%Cost to repair: $450Symptoms:
Green or yellow fluid under the car, temperature gauge erratic readings.
7. Faulty Rear Caliper
Occurrence: 8%Cost to repair: $550Symptoms:
Grinding noise from rear brakes when applying the brake pedal.
8. Faulty Rear Brake Pads
Occurrence: 7%Cost to repair: $200Symptoms:
Squealing or grinding noise from rear wheels when driving.
9. Rear differential seal leak
Occurrence: 6%Cost to repair: $350Symptoms:
Fluid leaking from the rear axle, whining noise from differential.
10. Faulty Front Oxygen Sensor Heater (FOH) Element
Occurrence: 5%Cost to repair: $220Symptoms:
Check Engine light comes on, poor engine performance.
11. Faulty Rear Wheel Bearing
Occurrence: 4%Cost to repair: $700Symptoms:
Rough idling, vibration from the rear wheels when driving.
12. Transmission leak or solenoid failure
Occurrence: 3%Cost to repair: $900Symptoms:
Slipping or hesitation from transmission, fluid leaking from the transmission pan.
13. Faulty EGR (Exhaust Gas Recirculation) system
Occurrence: 2%Cost to repair: $400Symptoms:
Rough engine idle, poor performance.
14. Faulty Knock Sensor
Occurrence: 1%Cost to repair: $190Symptoms:
Engine stumbling or hesitation, Check Engine light on.