Services / AdBlue and NOx sensors
AdBlue and NOx sensor repairs in Cardiff
An AdBlue warning with a countdown on the dash is not a suggestion. When it reaches zero the car will not restart. The good news is that it is usually a sensor, not the system.
What is included
- NOx sensor testing and replacement, upstream and downstream
- AdBlue metering unit, pump and injector diagnosis
- AdBlue tank level sender and heater faults
- SCR catalyst and system pressure testing
- Coding and adaptation of replacement sensors to the vehicle
- Emissions warning lights and limp mode cleared once the cause is fixed
- Countdown to no-start reset after a verified repair
- AdBlue fluid supplied and filled to the correct specification
What it costs
Priced once we know which component has failed, because a NOx sensor and an SCR catalyst are separated by an enormous amount of money. We test first and tell you which one you are looking at before you commit to anything.
How long it takes
Diagnosis is usually an hour or two. A sensor replacement is normally the same day. Anything deeper into the SCR system is quoted separately.
Which makes
All diesel makes. We see the most of this on Mercedes-Benz, BMW, Audi and VW group diesels from roughly 2015 onwards, which is where AdBlue became standard.
Ring the workshop with your registration and we will give you a price for your exact vehicle, not a range that turns into something else when you arrive.
AdBlue and NOx sensors, questions answered
My car says it will not restart in 500 miles. Is that real?
Yes, completely real. It is emissions legislation rather than a scare tactic, and when the countdown reaches zero the engine will not start. Get it looked at while you can still drive to us.
I topped up the AdBlue and the warning stayed on.
Then it is not the fluid. Most commonly it is a NOx sensor, the metering unit, or the level sender in the tank. Topping up again will not clear it, and the countdown keeps running.
Can you just delete or remap the AdBlue system?
No. Removing or disabling emissions equipment makes the vehicle illegal to use on the road and is an MOT failure. We will not do it, and anyone offering to is handing you a car you cannot legally drive.
Why are NOx sensors so expensive?
They are precision parts that live in the exhaust stream and they are usually only sold complete with their wiring and control module. We will always give you the genuine and the OEM option, because the price difference on this particular part is often substantial.
How long do NOx sensors last?
There is no fixed interval. Most fail somewhere past 60,000 miles, and short journeys shorten their life because the exhaust never reaches temperature. If yours has gone early, it is worth checking why.
Related services
DPF cleaning
Blocked diesel particulate filters cleaned, and the reason it blocked found.
Diagnostics
Dealer level equipment, and the experience to read what it is telling us.
Car servicing
Interim, full and major engine servicing, to the manufacturer schedule, logged in your car's digital service history.
Ring us about adblue and nox sensors
Tell us the registration and what it is doing. We will tell you what it needs, what it costs and when we can take it.
Cardiff and the Vale of Glamorgan. Drop the car at Cardiff Marine Village, Penarth Road.