The Ecu.

[forrestt]

ive read that if for example you had your iq remapped it would return back to stock after 'so long'. Is this true? Has toyota made a remap proof car?

And if it learns does it change the power delivery dependant on how you drive? Reason why I ask is because last night I did 44 mpg driving normally (keeping up with traffic) then tonight I managed 58mpg! But I was really taking it easy, keeping an eye on the real time mpg counter, making sure it was at 60 as much as possable (mine only goes that far (its a 58 plate) yet the work one goes to 99! Its a 10 plate) the longer I drove like my gran the easier it seemed to keep the mpg really high, did the ecu have anything to do with it or was I just getting used to driving slowly?

[MattIQ]

I don't know about the ECU, but your dealer should be able to perform the 'max 60mpg' instant reading fix to 99mpg by using part 83800-74081. (For free under warranty).

[forrestt]

Its no longer under warrenty :(