Cleaning · Diagnosis · Replacement
Limp mode, warning lights, a vehicle that will not start in a couple of hundred kilometres. These are two of the faults diesel owners fear most — and with good reason. But far from all of them need new parts. We work out what is actually wrong before anything is replaced.
The EGR system routes part of the exhaust gas back into the intake to lower combustion temperature and with it NOx emissions. That also means the valve works every day in hot, soot-laden gas.
Soot and oil mist gradually build up in the valve and in the intake manifold. On vehicles used mainly for short trips the deposits harden until the valve no longer closes fully — or seizes in the open position.
Typical symptoms:
What we do: We read live data, not just fault codes — that shows whether the valve actually moves, or is merely being asked to. If it is sooted up, it can often be cleaned and reused. If it is worn or electrically faulty, it gets replaced. We look at the intake manifold at the same time, because if the valve is clogged the manifold usually is too.
Important: The EGR system is a legal requirement. We do not remove or disable EGR on vehicles that are to be driven legally in Denmark — it is unlawful and means the vehicle cannot pass its roadworthiness test.
AdBlue is a urea solution injected into the exhaust, where it converts NOx into nitrogen and water vapour. The system is called SCR and is fitted to virtually every diesel from around 2015 onwards.
What makes AdBlue faults different is the consequence: the law requires that the vehicle cannot start if the system is not working. You typically get a countdown — "no start possible in 800 km" — and when it reaches zero, the vehicle stays put.
Typical symptoms:
What we do: We work out where in the system the fault sits. It is rarely the whole module. Far more often it is a NOx sensor, a blocked dosing injector or crystallised AdBlue causing a blockage. We test pump pressure, dosing and sensor values before recommending anything.
Call as soon as the countdown starts. As long as the vehicle still drives, it is an ordinary repair. Once it has stopped, it has to be transported — and that gets more expensive.
EGR, AdBlue and the particulate filter are three parts of the same system. If the EGR valve is stuck open, more soot goes into the particulate filter. If the filter does not regenerate, faults appear on the AdBlue dosing. And a poor injector can send enough soot through the system to ruin all of it.
That is why we do not simply replace the part the fault code points at. If the injectors are worn, the engine burns dirty, and the whole after-treatment system is loaded harder than it was designed for. You can have that checked for DKK 250 per injector — see dyseservice.
The price depends entirely on what is wrong — cleaning an EGR valve and replacing an AdBlue pump are a long way apart. You get a fixed quote before we start, and we do nothing you have not agreed to. We take all makes and model years.
No. The EGR system is a legal requirement on vehicles driven on Danish roads, and a vehicle without working EGR cannot pass its roadworthiness test. We clean, repair and replace — but we do not disable.
Call now, while the vehicle still drives. The countdown does not stop on its own, and topping up AdBlue does not help if the fault is in the system. If you drive until it reaches zero, the vehicle has to be transported to the workshop.
It depends on whether it is sooted up or worn. A sooted valve can often be cleaned and work fine afterwards. If the electrical control is faulty, or the valve seat is worn, it needs replacing. We measure before recommending anything.
Because the cause has not been found. An EGR valve that soots up again and again is usually down to something else — worn injectors burning dirty, a faulty turbocharger, or nothing but short trips. We look for the cause, not just the symptom.
Yes, it does. An engine that regularly reaches operating temperature for a sustained period burns off deposits and regenerates the particulate filter properly. If you only drive 10–15 km at a time, a longer run once a week is a cheap form of maintenance.
Yes. AdBlue systems are fitted to everything from cars to trucks and agricultural machinery, and we work with all of them.
Customers on Google
Really kind and helpful, can definitely be recommended. Had diesel injectors reconditioned and bought new ones … (translated from Danish)
… a very professional workshop run by father and son. The communication is clear and precise. The service is first class and the prices are honest. (translated from Danish)
Very good service. They know what they are dealing with, and they were quick. I will gladly come back. (translated from Danish)
