alt Hacker NewsThe deletes are for recirculation systems not DEF. Recirculation was always a bad idea and anyone who wants diesel for some reason should use DEF.
The deletes are for recirculation systems not DEF. Recirculation was always a bad idea and anyone who wants diesel for some reason should use DEF.
There are three main emissions control systems in diesels, the Exhaust Gas Recirculation (EGR), Diesel Particulate Filter (DPF) and Selective Catalytic Reduction (SCR) which uses Diesel Exhaust Fluid (DEF).
Any or all can be "deleted" and is a crime to do so. All 3 systems add complexity and potentially reduce performance which is why those who don't care about emissions like to get rid of them.
Before DEF NOx regulations steadily went up engine manufacturers relied on increasing amounts of EGR to control NOx until it was not tenable, once DEF systems where implemented they could back off EGR increasing performance but not as much as ripping it all out and tuning for no care of emissions.
There are EGR free engines that rely entirely on DEF to control NOx but they are not for on-road use in the US thus far.