How to explain the behavior of the ECU ?

[Quebecker]

Hi,

I will soon install an HHO kit on my wife's car. Before installing the kit ans Using a ScanGauge II, I started with the production of a consumer report.

In my first trip on the highway, I got a consumption of 9.8 liters / 100 km (24 MPG) and I immediately saw that it was abnormal. Remember, no HHO, just OEM :-)

During an investigation to find out what cables I should use to possibly hook up my EFIE, I disconnected the negative battery cable for over an hour.To my great surprise, after disconnecting the battery, I immediately noticed that the fuel consumption has improved. I made ​​another trip and got a consumption of 7.8 litres/100km (30 MPG) in similar conditions.

What could explain such an improvement? I have made ​​no changes to the car besides having disconnected the battery?

Thanks
Remi

[nst6563]

could depend on the the environment, weather conditions, etc.

I have a nissan Maxima and it's ecu works a little different in that simply disconnecting the battery doesn't seem to do anything but wipe radio stations.
There is a series of ECU resets that need to be performed which include reset to defaults, re-learn throttle position, idle speed, etc. When complete, the ECU is set into a "learning" mode in which you simply start the car, let it idle for about 30 seconds or a minute. In this time you can see things adjusting as the gauges move, rpm settles in, and the engine will overall run smoother. Then take it for a drive to complete the process.

I too have similar results as you when resetting the ECU but mostly after running an engine cleaning agent (I use Seafoam in the gas, oil, and intake) and then changing the oil I do a reset and things run much smoother. Same happens with seasonal changes from summer to winter.

It could be your ECU just has some "bad memories" contributing to "bad mileage"