Overview: 

The ECU (Engine Control Unit) or the computer that controls the engine will need to be reprogrammed in order to function properly with  the missing emissions hardware, DEF counter, and associated warning lights. 

The exhaust will need to be modified in order to remove the DPF (Diesel Particulate Filter). The DPF system is intended to remove ash and soot. Also it has a tendency to become plugged and fail, being one of the most “prone to fail” parts in the entire emissions system.

The EGR System (Exhaust Gas Recirculation) will be disabled in the ECU programming and at the minimum will need the pipe that ties into the exhaust blocked / blanked off. Additionally, some EGR off solutions may require the EGR valve to be unplugged. 

AdBlue is added to your exhaust and mixes with the exhaust gasses your car produces. It reacts with nitrogen oxide gas (NOx gas) created by your engine and breaks it down into nitrogen and water vapor. However, the Def fluid level sensor and DEF injector are known for failing, costing thousands to repair for vehicles out of warranty.  

Materials needed:

In order to flash your ecu, you will need some specific tools to read the file off of your ecu. Flashing tools such as MPPS, KESS, KTAG, TRANSDATA, PCM FLASH, and many more are intended to read the stock calibration data from the ecu and write it back. Original versions of these tools will run into the thousands and will require yearly subscription cost. Clone tools (non legitimate versions) can be found for a fraction of the price and many people (thousands of people) have had good luck using clone tools for flashing their ecu. The question of ethics is normally brought up when discussing clone tools and all I will add is there is no cost effective way to remap your car on your own without them. Clone tools can be found on Aliexpress and some other sites.

If you are working with EDC15 or EDC16 (ALH, BEW, or BRM)  Then MPPS V12+ will work fine. Honestly I still find that MPPS v12 or 13 are the most stable and cost effective. Although the version is old it is still fully functional on Windows 10 64bit.

Newer engine codes such as CBEA, CJAA, CKRA or any other late model common rail  engine  is equipped with a EDC17 ecu and will require the ecu to be removed from the car to read out the original calibration file. Alternatively if you have an original calibration file from another source that matches your software version you can flash your ecu without having to open it. Time permitting I will be making a file repository that may help save some time regarding original files. Tools that I would recommend with MED17 cars would be PCM Flash and Ktag.