DPF, EGR and AdBlue (SCR) are diesel emissions systems, each managed by ECU software. An "off" solution modifies that software. These solutions are supplied for legally permitted off-road, motorsport and diagnostic use only. On public roads, emissions equipment must stay working in most countries.
DPF (Diesel Particulate Filter)
The DPF traps soot from the exhaust and periodically burns it off in a cycle called regeneration. A DPF solution changes the software that manages this process. Workshops often see failed or blocked filters that put the car into limp mode, which is why the request usually comes alongside a diagnostic or off-road build.
EGR (Exhaust Gas Recirculation)
EGR routes some exhaust gas back into the intake to lower combustion temperature and reduce NOx. Over time the valve and passages can clog. An EGR solution modifies the related ECU control and makes sure the diagnostic trouble codes are handled correctly, so the car does not sit with a warning light or drop into limp mode.
AdBlue / SCR
SCR injects AdBlue fluid to convert NOx into harmless gases. The system is common on modern diesels and can be expensive to repair when the pump, injector or sensors fail. An AdBlue solution adjusts the software that manages the SCR system.
What "off" actually means
These are software changes only. No parts are removed by us, and nothing is welded or cut. A proper implementation leaves no residual fault codes and no warning lights, so the ECU behaves predictably. Done badly, an emissions edit can leave the car flagging errors, which is why calibration quality matters.
The legal side
Emissions-related modifications are restricted for road use in most jurisdictions, including across the EU. It is the customer's responsibility to comply with local road-traffic and emissions law. We build these files carefully for permitted off-road, motorsport and diagnostic scenarios, and we do not advise using them where the law does not allow it.
See the full list of options on the services page, or read how ECU file tuning works.
