hey guys here is caption from skylines downunder to doin it the ole 1,2,3 step, to better performance and fuel economy.........and yes they both work as i have done both steps and it is all good!
ECU Reset:
This is a very good procedure to follow, especially after making any changes to the car, for example after fitting a new exhaust, or air filter, or just every couple of months as part of a service routine.
To reset the ECU, disconnect your car's battery for 24 hours. This will reset the ECU to the factory defaults.
I have also heard that this can be done more quickly by disconnecting the battery and pressing the brake pedal (discharging any residual power in the car's electrical system), and then reconnecting the battery.
- It has been recently posted that this technique can help if done prior to a run down a drag strip, with a fuel tank of octane boosted petrol or #1 racing fuel.
- Apparently when the car is started for the very first time, the factory ECU advances the timing by about two degrees, and monitors the knock sensor. If any detonation is detected, the ECU will retard the timing by three degrees. It will continue advancing and retarding by progressively smaller increments. After a time, the ECU is doing the advance / retard by only tenths of a degree, and any power gains resulting from a tank of #1 racing fuel for example will take a long time to show, and not be noticeable. Resetting the ECU will cause the ECU to very quickly re-map the ignition curves when the car is restarted. The poster advises disconnecting the battery, pressing the brake pedal, and reconnecting the battery prior to staging.
A number of Skylines Downunder Club members have done this to their Skylines with good results. One friend reports a smoother drive, and more free revving. First impressions on it car is that it starts quicker (not that it ever cranked for more than a second or two), feels smoother in the low rev range, and seems to have a little more torque in low speed acceleration. Possibly better fuel economy also. It pays to reset after each modification to the vehicle, or soon after purchase to begin with...