Upstream O2 Sensor — Maruti Suzuki Swift
Category: Exhaust | Severity: high | Cost: ₹2,500–₹9,000
What is Upstream O2 Sensor?
Located before catalytic converter to measure raw exhaust oxygen.
How Upstream O2 Sensor Works
Helps ECU adjust air-fuel ratio before combustion cycle stabilizes.
Why is Upstream O2 Sensor Important?
Critical for engine performance and fuel efficiency.
Common Problems
- Sensor fouling
- Incorrect readings
Symptoms
- Engine hesitation
- Poor fuel economy
Causes of Failure
- Fuel additives
- Carbon deposits
Impact on Car Performance
Direct impact on engine tuning and power.
DIY Fix Guide — Step by Step
- Check OBD codes
- Replace sensor
Maintenance Tips
- Regular engine tuning
- Use clean fuel
Replacement Cost in India
Estimated range: ₹2,500 – ₹9,000
Where to Buy Online
When to Replace Upstream O2 Sensor
When ECU error code appears.