[svxistentialist]

Originally Posted by processengr

On the "learning mode" function of the ECU, what effect does the power light "mod" (connecting a switch to ground a pin on the ecu to engage the power map) have on the "learning" process?

That's a very good question Gordon and I don't know the answer or if the answer is available from any of the Subaru manuals we have. I'll hazard a guess.

The "learning" mode should probably be thought of as an automatic adjustment mode from the fuelling system. The software analyses data from the input sensors, and based on load and detonation and O2 information etc it adjusts to an optimal fuel mix based on the information it "sees".

So if you have been using low grade fuel, and the ECU has adjusted to using that, and you then fill up with high octane fuel, the ECU has to "learn" as you drive that it is now safer to load the engine more without risking detonation. Such an adjustment function will cause the timing to be changed in this instance.

These adjustments will continue to be assessed and reacted to, regardless of whether the gearbox is in normal mode or in power mode.

My guess would be that the ECU would learn to retard the ignition less while the car was running full-time power mode as the gearbox would tend to rev the engine higher in each gear, which is a lower load situation in regards to detonation.

Basically it would be doing the same job in either mode, just compensating for the different circumstances.

Joe