The early ECUs can be pretty quiet on the knock correction, but there is a way to persuade them to come to life, just as there is a way to persuade the later ECUs to bring up the Advance Multiplier after a reset.

Try driving the car between 3000 and 4000 RPM on *light* boost and *hold* it there (high gear needed, obviously). If you're running good fuel then you should see it rise slowly as the ECU gently tries more and more advance. Once this has been done and it settles on a value, it should seek toward that value much more quickly (ie it has learnt what it can do at that point in the map). Once it starts to learn in one part of the map it should start learning in others. It is pretty rare to see it add much, if anything at all, on high boost. It is also normal to see a little downward "blip" as it comes onto boost, if it's a rapid vacuum -> high boost transition (it's to try to catch transition det).


has anyone heard this before?
i mention it because my version 6 sti has decided to give me up to 3 degrees of positive knock correction when exelerating (on my secs dash).i thought that there may have been some knock and the ecu was trying to stop it.then i thought it may be the maf breaking down.ive also accused my previous tank of fuel of being sub standard.
ive disconnected the maf with the engine running and it stalls,i think this is right ??
ive emptied my fuel tank and refilled at my local pump,this made no difference to the knock correction.(still +3 degrees max )

could this be whats happened to my car ?

the information came from pat, is this the same pat from scoobyclinic ?