ECU Education

[AAH!]

Am I right in thinking that the ECU “learns” the engines running parameters and once the motuer fuse is pulled the it clears the ECU’s memory and the running parameters have to be relearnt and for a short time the engine can behave a little erratically?

If this is the case is there a better way to “break in” a freshly cleared ECU or for that matter a newly installed chip: Give it a good thrash for 50 miles so it knows what you want of it; or take it easy and gently build up and once settled in move on to the thrashing bit.

Depending on how you break the ECU in can it have a lasting effect on performance, mpg, smooth running, etc? At least untill the fuse is pulled again.

I know it isn’t as simple as that but does it make any difference?


Angus

[Graham]

A few years ago this was mentioned on the old S2Central forum, and if i recall you take it easy for a few miles so it effectively callibrates itself. I may be wrong though i am no expert.

[S2central.net]

Am I right in thinking that the ECU “learns” the engines running parameters and once the motuer fuse is pulled the it clears the ECU’s memory and the running parameters have to be relearnt and for a short time the engine can behave a little erratically?

If this is the case is there a better way to “break in” a freshly cleared ECU or for that matter a newly installed chip: Give it a good thrash for 50 miles so it knows what you want of it; or take it easy and gently build up and once settled in move on to the thrashing bit.

Depending on how you break the ECU in can it have a lasting effect on performance, mpg, smooth running, etc? At least untill the fuse is pulled again.

I know it isn’t as simple as that but does it make any difference?

Angus

Well I don't claim to know all the inner workings on this, but I can't see how the ECU could adapt properly if the engine was only tootled around with light throttle below 3000rpm - so yes you do need to drive the car properly if the ECU is to get a chance to adapt across the engines dynamic range.

Note - there is no adaptation at WOT IIRC - but whilst lambda is active then the ECU is learning about water temp, air temp, air pressure, fuel quality etc etc

[porkkis]

Ecu learns the lambda adaptation and idle adaptation values. Not aware of any others. So no temps etc afaik.

[AAH!]

I can't see how the ECU could adapt properly if the engine was only tootled around with light throttle below 3000rpm - so yes you do need to drive the car properly if the ECU is to get a chance to adapt across the engines dynamic range. Note - there is no adaptation at WOT IIRC -

What difference would it make if you did just tootle around? Also Paul- what do you mean when you say "there is no adaptation at WOT". Do you mean that you should give the car a bit of a work out across the range but not at WOT?

I can't quite remember the details and that is why I am asking, bit I think that after doing my custom map and replacing the chip Mihnea said give it a thrash on my way home.

[S2central.net]

Yeah what I mean is the ECU runs directly from the fuel map at WOT - it doesn't bother listening to lambda values and try to regulate a perfectly stoich mixture... this allows the mixture to be on the rich side at WOT to ensure best performance.