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  ECU Tuning What is ECU/Chiptuning

What is ECU/Chiptuning

This is the million dollar question on everyone’s mind. What is ECU/Chiptuning and how is it possible to extract more performance from a completely stock engine and what is the process in which this is achieved.
The answer is quite simple given the fact that modern vehicles are controlled by computers it allows for tuning companies like AQ Tuning to modify the data within the ECU to draw more power over the manufacturers stock settings.
When vehicle manufacturers were forced to meet stricter emission laws the dawn of Electronic Fuel Injection systems was born which resulted in finer burning and fuel efficient combustion engines.
This created a backdoor for tuning companies to modify the data within the Engine management system to not only extract more power but also save on fuel consumption especially diesel powered vehicles.
Chip tuning refers to changing or modifying an erasable programmable read only memory chip in an automobile's or other vehicle's electronic control unit (ECU) to achieve superior performance, whether it be more power, cleaner emissions, or better fuel efficiency. Manufacturers generally use a conservative electronic control unit map to allow for individual engine variations as well as infrequent servicing and poor-quality fuel. Vehicles with a remapped electronic control unit may be more sensitive to fuel quality and service schedules.
This was done with early engine computers in the 1980s and 1990s. Today, the term chip tuning can be misleading, as people will often use it to describe ECU tuning that does not involve swapping the chip. Modern electronic control units can be tuned by simply updating their software through a standard interface, such as On Board Diagnostics (OBDII). This procedure is commonly referred to as engine or electronic control unit tuning. electronic control units are a relatively recent addition to the automobile, having first appeared in the late 1970s.
As technology advanced, so did the electronics that go into cars. The electronic control unit in a modern automobile, together with advanced engine technology, makes it possible to control many aspects of the engine's operation, such as spark timing and fuel injection. The electronic control unit may also control electronic throttle control (drive-by-wire), poppet valve timing, boost control (in turbocharged engines), Anti-lock braking system, the automatic transmission, speed governor (if equipped), and the Electronic Stability Control system.
Performance gains are realized by adjusting the ignition timing advance. Higher timing may result in higher performance. However, to cope with advanced timing, one must run high-octane gasoline to avoid pre-ignition detonation or pinging. Manufacturers design for a specific timing and this may limit performance accordingly.
In addition, changing fuel maps to coincide with the stoichiometric ratio for gasoline combustion may also realize performance increase. Most manufacturers tune for optimum emissions and fuel economy purposes which can limit performance.
Cars with a turbo fitted can have the requested and allowable boost levels raised, these applications usually have the most effect if the turbo fitted is a low pressure turbo which leaves the most room for improvement.
Another reason to change the electronic control unit map is if there are engine, intake, or exhaust modifications to the car. These "bolt-on" modifications alter the way that the engine flows, often causing the air to fuel ratio to change. Without re-mapping the fuel tables, some of the performance gains from the modifications may not be realized.
A poorly tuned electronic control unit can result in decreased performance, driveability, and may even cause engine damage.
The most common way to "upgrade" the electronic control unit is using either plug in modules as mentioned above or using a specialist tuner who will use an On Board Diagnostics Flash tool. These devices generally plug into the diagnostic port although in some cases the reprogramming is done directly on the circuit board. Maps are supplied by tuners.
An alternative to modifying the on-board chip is adding an external device, often known as a tuning box. The abilities of the external devices generally reflect on-board chip modifications, with the advantage that they can be easily removed to restore the vehicle to standard. Adding an external tuning box is generally only possible on modern engines with external management ports.
Please note Tuning boxes or Piggy back tuning should only be done when its not possible to tune the original electronic control unit.
The most difficult concept to grasp for most people is that remapping is merely engine tuning, albeit that it's being done electronically rather than mechanically.
A 'chip' is simply an electronic storage device or EPROM which is located on a circuit board inside the ECU (the Engine Control Unit).
The chip contains values in a hexadecimal form which the ECU's main processor (another device on the same circuit board) can understand and use to control the engine.
Each value inside the chip is held in its own separate position (known as an 'address'), and due to the way manufacturers develop many engine on the same unit and to fit into tax bands, engines are detuned to fit into these bands and achieve the manufacturers desired place into the market.
As a result the car never performs as well as its mechanically controlled counterpart from the factory...
When a car is remapped, we are basically altering the values at the groups of addresses that control fuelling, ignition timing and on turbo engines, turbo boost, there are many other tables we change to allow for this to scale with other systems that most other tuners miss whilst they search for gimmicky trial solutions.
Naturally, this is a complex and skilled operation. It requires experienced personnel who understand the hardware and software, and of course have the appropriate electronics qualifications in order to understand the procedures.
Nowadays the technology is becoming even more complex. Gone are the days of the 28-pin plug in chip, a simple 8-bit device. We've experienced the occasional wake-up calls from chips soldered to the circuit board and with unusual sets of contents, and have now moved into territory which is definitely not for the faint hearted.
Modern engines such as the V.A.G. 1.8T and Audi TT have ECU's with 16-bit 44-pin devices, surface-mounted to the circuit board. Not just new hardware on the outside but also some mind-boggling software on the inside. Luckily, AQ's engineers have kept abreast of the technology, and the company has invested heavily in state of the art de-soldering equipment, data-logging and remapping software. We do not, therefore, have to rely on modem-downloads from any other source, all the AQ software is written here and you see the price saving according.