Oxygen sensor replacement
A lambda sensor measures residual oxygen in the exhaust and lets the control unit meter fuel accurately.
Symptoms
- The mixture runs rich, fuel use climbs, the catalytic converter degrades, exhaust smells of fuel.
What's included
- As it ages, its response slows: the mixture becomes rich, consumption rises, the catalytic converter is damaged and the exhaust smells of fuel. There are usually two sensors, before and after the catalytic converter, with different tasks, so it is important to replace the failed one. We check the signal graph in live data: the curve shows whether the sensor has actually failed or is reporting a real mixture issue. Installation uses heat-resistant thread lubricant, and we monitor fuel trims after replacement. Lambda-sensor replacement in Kyiv follows a signal-graph check rather than a single fault code.
Additional checks
- Lambda sensor signal graph in live data
- Fuel trims after replacement
Why it matters
There are usually two sensors — before and after the catalytic converter — with different jobs, so only the failed one is replaced. The signal curve's shape shows whether the sensor is dead or reporting a real problem.
More details
The lambda sensor (oxygen sensor) measures the residual oxygen in the exhaust and lets the control unit dose fuel precisely. As it ages, its response slows down: the mixture goes rich, fuel consumption rises, the catalytic converter suffers, and a fuel smell appears in the exhaust. There are usually two sensors — before and after the catalytic converter — and they have different jobs, so it's important to replace the specific one that has failed. We check the signal trace in the live data: the shape of the curve shows whether the sensor is genuinely dead or whether it's reporting a real mixture problem. We install it with heat-resistant thread compound and check the fuel trims after replacement. We replace lambda sensors in Kyiv only after checking the signal trace, not on a single fault code alone.
Need a Technician Consultation?
Describe the vehicle and symptoms, and we will suggest which check to start with.
Book a Diagnostic