what does the ecu learn after you reset it?

[Michelson4301]

After battery is disconnected Fuel economy will change on the Mass air flow based vehicles until the barometric pressure/pseudo map term is learnt. With MAP based vehicles this is instantaneous when ignition is turned "on".

 

[Not_An_Abba_Fan]

This is funny.....

A reset of the ECU just resets it back to factory default settings, nothing more. On pre VT vehicles you can reset the IAC by revving to 2000 rpm for 10 seconds, but post VT they self learn anyway. The ECU doesn't "learn" it uses it's pretuned maps and fuel trims to compensate for certain driving styles. If you drive like a hoon, the ECU will tend to hold gears longer in an auto, if you drive like a granny it will change quicker. The only way to alter the ECU tune permanently is to get a remapped memcal.

 

[moff_man]

a reset ecm sets things back to base settings, ie new plugs new oil new air cleaner, than it adjusts its self as the parts wear. newer ecm's in the vz and ve's have what is called a fuzzy logic which learns in real time. vr vs ecm have not thay are rom (read only memory) newer ones have ram (random access memory ) and is able to be written and rewritten for sofwere upgrades etc

 

[Andrew426]

The power button only delays the shifts and gives a little bit more power. Does not do the same thing as a tune though.

Not quite. PWR button only moves shift points about and increases shift pressures. It doesnt make the engine any more powerful.

 

[Michelson4301]

This is funny.....

A reset of the ECU just resets it back to factory default settings, nothing more. On pre VT vehicles you can reset the IAC by revving to 2000 rpm for 10 seconds, but post VT they self learn anyway. The ECU doesn't "learn" it uses it's pretuned maps and fuel trims to compensate for certain driving styles. If you drive like a hoon, the ECU will tend to hold gears longer in an auto, if you drive like a granny it will change quicker. The only way to alter the ECU tune permanently is to get a remapped memcal.

Yes I am aware and understand what you are saying. I am merely pointing out that the Base setting for the pseudo map term that the VS/VT/VX/VT V6 pcm's use for calculations is usually too low and requires a little driving time to learn up to were it should be. This is the altitude correction factor that DOES effect base fuelling although the oxygen sensors do trim this back to stoich at cruise and this trimming DOES change your full throttle AFR's So long as LTFT cell 16 (or actually labelled15 which ever way you look at it) has had correction applied to it.

All of the ECM/PCM's used by holden learn to some extent to accomodate for wear and general conditions, usually all this is lost when you disconnect the battery. All the LTFT's, PAM's, KAM's, IAC ACC steps are set back to base settings. This is why a car may shift the auto hard or slip on changes, why the engine may hunt for idle, go high or stall and why fuel economy can be brilliant or piss poor BUT only until every system has had sufficent time to carry out what has been labelled in OBD2 vehicle systems a drive cycle.

OBD2 Fault codes are a whole different kettle of fish.

 

[moff_man]

the vr v6 leans out at cruise to 17:1 thats why they good on fuel, also it wont do it unless the temp is correct

 

[letthiswork1]

Wrong forum post XD Ignore my comment haha