Knock Sensor — Audi A4
Category: Engine | Severity: high | Cost: ₹3,000–₹12,000
What is Knock Sensor?
Detects engine knocking or detonation.
How Knock Sensor Works
Sends signals to ECU to adjust ignition timing.
Why is Knock Sensor Important?
Prevents engine damage due to knocking.
Common Problems
- Sensor failure
Symptoms
- Knocking sound
- Reduced power
Causes of Failure
- Wear
- Electrical issues
Impact on Car Performance
Engine may run inefficiently or get damaged.
DIY Fix Guide — Step by Step
- Check ECU codes
- Inspect sensor
- Replace if faulty
Maintenance Tips
- Use good fuel
Replacement Cost in India
Estimated range: ₹3,000 – ₹12,000
Where to Buy Online
When to Replace Knock Sensor
Replace if sensor fails.