ecu reset/learning 2002 sti
 

can anyone tell me how fast the standard ecu updates itself.

basically when i bought the car i was running it with bp ultimate for 2 weeks, however after i discovered how crap ultimate is i now only run tesco 99 or ultimate , but mainly tesco.

ive also re fitted standard re circ and removed blitz vta .

so its been a few weeks now from ive been running good fuel, so will the ecu already have re learned as such the new fuel and my driving style.
or will i need to reset it completely.

i will be getting it mapped in the new year so it will be reset then anyway , if this is correct ?

thanks

There are hundreds of answers to that question, depending on which parameters you're asking about. Some are recalculated hundreds of times a second, others can theoretically take weeks to refresh.

In practice, on a newage ECU, yes, they're normally quite proactive to fuel quality - so it will be most likely to be "over" the Ultimate(not) by now.

It should in practice have reacted to the refitting of the standard dumpvalve instantly, purely because it wouldn't have actually had to relearn anything there, it will respond directly to the slight alterations in mass airflow sensor readings caused by the change back to the recirc valve.

If you want to know what the ECU's doing in response to changes in fuel used and so forth, you can find out easily via a laptop, some freely downloadable software and less than a tenner spent on a diagnostic interface. Knowledge (especially in this case) equals power. :thumb:

In practice the mapper wouldn't have to reset the ECU if he didn't want to (and there are occasionally circumstances where this might be the case), but in most cases, yes, that would usually be true.

As above tho you can reset the ECU yourself with access to the right kit.