Home › Services › O2 / Lambda Sensor
From £80 · Open Monday to Saturday in Fenton
A slow lambda sensor feeds the ECU bad data, so the fuelling drifts, the idle hunts and the engine light comes on. We remove the sensor, clean it, refit it and reset the adaptations, often avoiding a replacement.
Fault codes read first
Sensor removed and cleaned
Adaptations reset
We’ll tell you if it needs replacing
Get a free quote
Tell us the reg and what the car is doing. We’ll come back with a straight answer and a price.
2,500+
Cleans completed
From £200
On-car DPF clean
Open Monday to Saturday
Fenton workshop
UK-wide
Postal DPF cleaning
How it works
The lambda (oxygen) sensor measures the oxygen in the exhaust and reports to the ECU many times a second, so it can keep the air-fuel mix right. Oil mist and soot coat the sensor tip over time, slowing its response and throwing the fuelling out.
We check the live data first to confirm the sensor is slow rather than failed. Then we remove it, soak the tip in an oxygen-safe decarboniser and loosen the stubborn deposits, before refitting it with fresh anti-seize and resetting the adaptations.
If the sensor has a broken heater circuit or an open-circuit fault, cleaning won’t help, and we’ll tell you it needs replacing.
Confirms the sensor is slow, not failed.
Taken out carefully so the ceramic element isn’t damaged.
Soaked in an oxygen-safe decarboniser.
Refitted with fresh anti-seize and adaptations reset.
Dashboard with the engine warning light on
Reading the fault codes before any work
Checking live data on the diagnostic tablet
Why it matters
A lazy sensor makes the ECU over-correct, so the fuelling drifts rich or lean, the idle hunts and fuel use goes up. Fault codes such as P0130 or P0171 often appear.
Left alone, unburnt fuel reaches the catalytic converter and makes it run too hot, and the DPF works harder too. Cleaning the sensor before it fails protects the cat and is usually much cheaper than a new sensor. Accurate readings also help keep emissions within MOT limits.
Lambda sensor cleaning starts from £80. Prices shown are starting prices. The final price depends on many factors, including the vehicle and how complex the job is, and we confirm it before any work starts.
We read the fault codes first, so you know whether it’s the sensor or something else before any work starts.
Vehicles
High-mileage commuting, oil mist and short town trips clog some oxygen sensors faster than others.
Town driving coats the pre-cat sensor, and the ECU flags P0131 and runs rich.
Oil mist slows the sensor’s response, the idle hunts and an emissions warning appears.
Long service intervals foul the front sensor, the trims hit their limit and P0171 appears.
Short trips foul the post-cat sensor, causing false catalyst codes and an MOT readiness fail.
Delivery idling carbons up the sensor, and the van drops into reduced power.
Direct-injection soot slows the sensor, the ECU runs rich and fuel use rises.
Service
DPF Cleaning & Regeneration
On-car, off-car and postal DPF cleaning with a controlled forced regeneration.
Service
EGR Valve Cleaning
Carbon-clogged or sticking EGR valve stripped and cleaned. From £120.
Service
Engine Carbon Cleaning
Hydrogen carbon cleaning for intake, valves and turbo passages. From £100.
Remapping and AdBlue
We work alongside our sister companies. ECU remapping is done by Pro Remapping, from the same Fenton workshop, and AdBlue and NOx faults are handled by AdBlue Specialist.
What does a lambda (oxygen) sensor do?
It measures the oxygen in the exhaust gas and reports to the ECU every few milliseconds. That lets the ECU fine-tune the fuelling so the engine stays at the right air-fuel ratio.
How do I know if my O2 sensor needs cleaning or replacing?
If the live data shows the sensor switching slowly but still within its voltage range, or codes such as P0130, P0136 or P0171 appear after idling or short trips, a clean usually restores its response. A broken heater circuit or open-circuit fault needs a new sensor.
Is it safe to clean a lambda sensor?
Yes, when it’s done off the engine with an oxygen-safe decarboniser. We don’t use acids or wire brushes that could damage the ceramic element.
How long does it take?
It depends on the vehicle and how easy the part is to get to, so we’ll give you a time when you book. Same-day slots are often available if we have space.
Does a cleaned sensor help with the MOT?
It can. A responsive sensor lets the catalytic converter work properly, which helps keep CO and HC readings down, a common reason petrol cars fail the emissions test.
How much does lambda sensor cleaning cost?
Lambda sensor cleaning starts from £80. Prices shown are starting prices. The final price depends on many factors, including the vehicle and how complex the job is, and we confirm it before any work starts. It’s usually much less than a quality replacement sensor. Call or message us for a quote.
How often should lambda sensors be cleaned?
There’s no fixed interval. Petrol cars doing lots of short trips may need it every 40,000–60,000 miles. On diesels, it’s worth checking if fuel use rises or oxygen sensor codes appear.
Do you offer a mobile service?
No. All our work is done at our Fenton workshop in Stoke-on-Trent, where we have the equipment to diagnose the fault and check the results properly. We’re open Monday to Saturday, with same-day slots when there’s space.
Call or WhatsApp us with the reg and the fault codes or symptoms, and we’ll tell you whether a clean will help.
201 King Street, Fenton, Stoke-on-Trent ST4 3ER · Open Mon–Sat 9am–6pm, closed Sunday · Visits by appointment