Emissions Solutions & Diesel Fault Diagnosis
AdBlue • DPF • EGR • NOx • SCR • Swirl Flaps • Catalyst Faults •
AdBlue • DPF • EGR • NOx • SCR • Swirl Flaps • Catalyst Faults •
Serving Newport, Caldicot, Chepstow, Monmouth, Cheltenham, Gloucester, Bristol, and all surrounding areas in South East Wales & Gloucestershire
Modern diesel vehicles rely on complex emissions control systems to reduce exhaust emissions and meet manufacturer and environmental standards. While these systems play an important role, they can also become a source of expensive faults, warning lights, reduced performance, poor fuel economy and persistent limp mode issues.
At ExTech Tuning, we provide professional emissions system diagnostics and fault-finding for cars and vans across Bristol, Gloucestershire, Newport, Monmouthshire and the surrounding areas.
Using dealer-level diagnostic equipment and extensive experience working with modern diesel engines, we help identify the root cause of emissions-related problems and provide practical solutions designed to restore reliability, drivability and vehicle performance.
Whether you're experiencing an AdBlue warning, DPF blockage, NOx sensor fault or EGR issue, we'll accurately diagnose the problem and advise on the most suitable course of action.
Common Emissions Problems We Diagnose
Many diesel vehicles suffer recurring emissions system faults, particularly on vehicles used for short journeys, stop-start driving, or high-mileage operation.
Common issues include:
Engine management lights
DPF warning lights
AdBlue countdown warnings
Excessive regeneration cycles
Reduced power or limp mode
Poor fuel economy
Failed MOT emissions tests
Turbo performance issues
Fault codes returning after repairs
Excessive smoke or poor running
If you're experiencing any of these symptoms, our advanced diagnostics can pinpoint the cause before unnecessary parts are replaced.
AdBlue & SCR System Solutions
AdBlue and SCR (Selective Catalytic Reduction) systems are designed to reduce NOx emissions. However, faults within the system can quickly become costly and inconvenient.
Common AdBlue faults include:
AdBlue malfunction warnings
Engine restart countdowns
Failed NOx sensors
Urea injector faults
Crystallisation issues
AdBlue pump failures
SCR efficiency faults
We provide thorough system diagnostics to identify the underlying issue and recommend the most effective repair strategy for your vehicle.
DPF Solutions & Diagnostics
The Diesel Particulate Filter (DPF) is one of the most common causes of diesel vehicle problems.
Blocked filters can restrict exhaust flow, reduce performance and trigger warning lights.
Our DPF services include:
DPF diagnostics
Forced regenerations
Live data analysis
Backpressure testing
Sensor testing
DPF cleaning recommendations
Root cause diagnosis
Where possible, we always aim to restore the existing filter through proper diagnosis and cleaning rather than recommending unnecessary replacement.
For heavily blocked filters, ongoing fault conditions or repeated regeneration failures, we can advise on the options available for your specific vehicle.
Learn more about our dedicated DPF cleaning service.
EGR Valve Solutions
The Exhaust Gas Recirculation (EGR) system helps reduce emissions by recirculating exhaust gases back into the engine.
Over time, EGR valves can become contaminated with carbon deposits, resulting in:
Hesitation
Reduced performance
Poor fuel economy
Excessive smoke
Engine warning lights
Limp mode activation
We diagnose EGR faults accurately and provide guidance on the most appropriate repair solution.
NOx Sensor Diagnosis
NOx sensors are increasingly common on modern diesel vehicles and can cause persistent fault codes when they fail.
Symptoms can include:
AdBlue system warnings
Reduced engine performance
Increased fuel consumption
Engine management lights
Emissions system faults
Our diagnostics process allows us to determine whether the sensor itself is faulty or whether the issue originates elsewhere within the emissions control system.
Swirl Flap & Intake System Problems
Swirl flaps are designed to improve combustion efficiency at lower engine speeds.
As vehicles age, these components can wear, stick or fail, leading to:
Loss of power
Uneven running
Increased emissions
Engine warning lights
We can diagnose swirl flap faults and advise on suitable repair solutions.
Catalyst & Efficiency Fault Diagnosis
Catalytic converter efficiency faults can be caused by multiple issues including:
DPF restrictions
Sensor failures
Air leaks
Fuelling issues
Engine management faults
Replacing a catalyst without identifying the underlying cause often leads to continued problems.
Our diagnostic process focuses on finding the true source of the fault before expensive components are replaced.
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Yes. We diagnose AdBlue, SCR, NOx sensor and related emissions system faults across a wide range of diesel vehicles.
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Yes. A heavily restricted DPF can reduce engine performance and trigger limp mode as a protective measure.
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Yes. We offer diagnostics and can advise on the most appropriate DPF cleaning solution depending on the condition of the filter.
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Absolutely. We specialise in tracing the root cause of repeated emissions-related fault codes and warning messages.
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We work on most cars and light commercial vehicles including BMW, Audi, Volkswagen, Mercedes-Benz, Ford, Land Rover, Jaguar, Vauxhall, Peugeot, Citroën and many others.
Important Notice
UK legislation prohibits the removal, deletion or disabling of factory-fitted emissions control systems. Vehicles modified in this manner may fail an MOT test and may not comply with road traffic or environmental regulations.
Customers are solely responsible for ensuring that any vehicle modifications comply with the laws applicable in their country of use.
ExTech Tuning accepts no liability for the use of software modifications that alter, disable or remove emissions-related systems where such use is prohibited by law.