Known tuning methods

First we need to understand what the ECU is and how this very important component controls the performance of your engine. The ECU (Electronic Control Unit) is the computer control unit that electronically manages the engines timing settings, fuel and oxygen supply by receiving signals from strategically placed sensors and managing settings to optimise the engine’s performance. The ECU is factory set when your vehicle leaves the factory, however drivers wanting higher performance have always been looking for ways to improve on the factory set performance of their engine. So lets look at how ECU tuning has evolved.


When vehicles started to use ECU units, one of the most obvious ways to tune an engine was to re-flash the EEPROM. Back in the early years the EEPROM was the unit that contained the map files. To tune a car ECU tuners needed to remove the ECU from the vehicle, open the ECU, de-solder the EEPROM unit, connect the EEPROM to a special device that was able to read and write the map files. The Tuner would take a full backup, which becomes a rollback point. Once the re-flash was done the Tuner would re-solder the EEPROM back onto the circuit board, re-seal the ECU housing and put the ECU back into the car.
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Biggest disadvantage: only the best Tuner’s could survive as it was a very risky operation and many amateurs turned the ECU into a brick.


This solution was the first “piggyback” tuning available. Basically it involves installing a 3rd party single chip on the circuit board inside the ECU. The person in the garage, who didn’t have to be an experienced Chip Tuner, removed the original chip from the circuit board and replaced it by a 3rd party chip that did something differently.
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The advantage of chip installation was that anyone could install the chip, however nobody knew what the chip did or how it worked exactly – basically it is a “blackbox” solution.
Biggest disadvantages: it can never be customised. It is an off the shelf solution: whatever it does, it does for all vehicles in all situations.


This is basically an advanced piggyback solution but nobody really knows what parameters this solution modifies and how. Some of the piggyback boxes are configurable but mainly you can only change fuel rail pressure, sometime boost and that’s it. For this particular reason, it is not customization of the engine management system, going further it is pointless to express yourself about what you want to achieve as because piggyback tuning boxes will deliver the same to all customers no matter what. The installation itself is easy(and meant to be easy for sales reasons). You simple open the package you receive from e-bay or TradeMe and you install it yourselves in your car by following the instructions. Piggyback tuning has evolved a lot. Now you can buy complete tuning boxes from everywhere, and there are some very good brands made in Germany. However, all are still a piggyback aftermarket tuning box that bypasses the ECU or manipulates the sensor signals in an unknown way.
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The advantage: easy installation.
Biggest disadvantage: while this may seem a cheap way to improve performance, the changes made to your ECU may not be ideal for your engine and you are unlikely to get the real performance benefits you want – and can get!


This is the advanced version of the EEPROM re-flash. Only qualified technicians can do this effectively, and these are technicians who have extensive knowledge and experience not only in diesel and petrol engines but also in Information Technology, communication protocols, programming languages, tuning software’s, etc and ideally have been actively involved in all the stages of ECU tuning over the past 10 years. So what is the re-mapping process?

There are many-many methods to read and tune an ECU however there are the 2 main techniques:

Reading and writing via OBD service port: the tuner connects to the OBD or OBD2 port with a laptop, reads out the map files from the ECU, (sometimes even without opening the bonnet of the car), then he modifies the map files to the vehicle and the driver’s requirements before uploading the modified map files back into the ECU. The Tuner also takes a full backup, which becomes a rollback point.

Boot mode: the tuner needs to remove the ECU from the car, opens the ECU, makes a connection to the ECU programming points and reads the map files. Then he modifies the map files to the vehicle and the driver’s requirements, before uploading the modified map files back into the ECU. The tuner also takes a full backup, which becomes a rollback point out that way. Once it’s all done the tuner needs to reseal the ECU housing and refit the ECU into the vehicle.
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Advantages: with ECU re-mapping you get a customised performance modification that changes the turbo pressure, injection timing, injector opening duration, air fuel ratio, torque limiter, speed limiter, RPM ranges, and other settings in the map files. These modifications optimizes the engine and ultimately raise the power (HP) and torque (N.m) limits of the engine.

The disadvantage of this solution is that you cannot do it yourself – you have to take your vehicle to a specialist who has the knowledge to re-map the ECU.

A high performance ECU re-mapping remap by a qualified Tuner come with an investment, however the advantages will be obvious to you by now.

Both EEPROM re-flash and ECU re-mapping solutions deal with any risk of bricking the ECU  by taking a backup. This is an essential step. Also this solution enables the Tuner to customize the tuning based on the customer’s requirement. Apart from the fact that everybody uses their vehicles for different purposes (we need to understand your needs) the tuner can also consider road condition/weather condition/fuel quality factors as well.

We at Xtremetuning only do ECU re-mapping. We are qualified Computer Software Developers with ECU remapping skills, not dealers. We reprogram vehicles and we don’t trade with piggyback units. We prefer professional workmanship over dealership, quality over quantity and yes, it has a PRICE. However, when you are considering a high-performance tune, we see this as an investment in your driving experience.