ECU Reprogramming

During those good 'ol days, when cars like Alfa Romeo Giulia, Datsun SSS, Fiat 124ST, etc.. ruled the streets I was still a teenager in a technical secondary school. After graduation from tertiary education I only could afford a 'poor man's Alfa Romeo'.

The only inputs to alter engine performance at that time was a mechanical actuator based on centrifugal force in the distributor which advances ignition timing as the engine RPM increases and a vacuum actuator to retard ignition timing when the accelerator pedal was released.

My first Honda [poor man's Alfa-Romeo] - yr 1979 stratified charged 1.5 liter 12v Civic (sold 1n 1983)

Improper ignition timing would induce 'explosion' or/and 'knocking'. A krypton timing light was normally used to correctly set ignition timing. Sometimes a few more degrees offset from the 'correct setting' to advance or retard sesedap rasa. Spark plug and contact point gaps were also adjusted by trial & error to squeeze out every fraction of bhp. For those who were willing to spend more gallons per mile invested on Weber carburetors.

Then around 1980's electronic ignition was introduced in this country for car engines to vary the timing to a greater degree than a fixed ratio advance curve.

My 2nd Honda [poor man's BMW] - yr 1983 has electronic ignition (sold in 1994)

A complete 'map of variables' was entered into the ignition program and preset timing would be read from a table. Later with the advent of modern technology and introduction of programmed fuel injection, cars have been made smart and their performance tuning has been made even simpler.

My first car with programmed fuel injection engine...yr1994 (well kept and still running)

Today engine tuning can be performed via microprocessors or computers. Car engines can be made more efficient, producing more torque [and power] and become economical as well as far as fuel consumption is concerned. This all results can be achieved by reprogramming car's ECU or 'firmware upgrading' or whatever terms you may call it.

My 5th Peugeot - yr 2008 308T , my first attempt on Turbo Car ....

Now air temperature, engine speed, engine load and even control over turbo waste gate control means that precise management of the engine ignition timing is possible and the optimum output throughout the rev range can be achieved.

What is ECU reprogramming
Different car's performance parameters are now judged by sensors embedded at various places in the car. These parameters may include ignition timing, fuel consumption, air flow, throttle position, crank position e.t.c.

All these are closely monitored via sensors and their performance reports are send to car's engine management system or electronic control unit (ECU). So ECU basically is a software program which process the signals send by the sensors and helps in better performance of the car in any given condition.


Why need ECU reprogramming?
Of course for better engine performance...
The car manufacturers do not always tailor make their ECU settings at optimum performance level. It may sound ironic or weird for all car enthusiasts but its a fact. The logic behind it is that the production cars are also aimed for all the end users and make sure that their product is well enough for almost every condition.

ECU reprogramming can be done by just overwriting the existing program and replacing it with a more tuned software to fit for purpose. Previously was done by removing the existing chip containing the software with a 'super chip' . Today, it has been made easy after the advent of serial port reprogramming, and now ECU reprogramming can be performed by just plugging and overwriting engine map by a better 'firmware'.

Reprogramming ECU can be a simple performance upgrading by pro-tuners but it may become complicated to some tuners who are not aware of the car's specification including transmission and would end up in creating a mess because they do not pay consideration on 'how the car engine is going to behave' under endurance.

ECU reprogramming may have some fuel implications if you want to squeeze out every remaining pony available. However 308T car can be tuned to an optimum level, a compromise to save fuel and raise the torque as well. It is believed to achieve an increase of around 30% in max torque... but how the torque curve is going to be is another story.

Why wouldn't I go for ECU firmware upgrade yet?
The answer is ... "still analyzing a few options available..."