| Author | Message | |||
     Id073897 |
It's a bit academic question, but anyone who knows how to keep the ECM from learning a new AFV? If I understand correctly, all the instant AFV calculated in closed loop cruising mode are summarized and used in open loop too. This might lead to (too) rich or lean spots in open loop if for example muffler or airbox are modified. I know that disconnecting the o2 sensor would lead to a similar result, but I thought, just "unflagging" a bit in the ECM would do that, so I get best of both worlds: adaption to changing air pressure while cruising and, by setting the apropriate AFV, eliminating misfueling in open loop. Any idea how to manage this? Regards, Gunter | |||
| Al_lighton |
Gunter, Supposedly, disconnecting the white Vehicle speed sensor wire into the ECM (not the center tab wire, the OTHER white wire) will prevent the AFV from learning. I haven't tested it, but Davo has. The problem is that there isn't a way to poke a particular AFV value into the ECM prior to preventing it's learning, other than by resetting the ECM to 100. Al | |||
| Id073897 |
Al, this is a very interesting approach and would be an easy resolution, I will go and try it that way. I never thought about the white cable. Writing a particular AFV into the ECM isn't too difficult. Well, okay, once you know how to :-) Thanks a lot! Regards, Gunter | |||
| Id073897 |
Self comment: seems not to work as expected. Please see attached file. Dyno shows new model 2007 airbox cover on a 2003 XB9R, freshly changed and after calibration. Using K&N, race ECM, stock muffler, white cable removed (if necessary at all). Blue line shows before, red line after calibration. (1PS = 0.735 kW) Regards, Gunter
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dyno XB9R 2003 w/ 2007 airbox