What causes timing to jump while decelerating w/no throttle?
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What causes timing to jump while decelerating w/no throttle? What cause that to happen? I thought the PCM was supposed to use the base table, but instead it will do that for fractions of a second, and then drop to some much lower number (10 degrees or more soemtimes), then jump back up. Pretty much, it does whatever it wants.
Are you sure this isnt DFCO. while the car decels in gear and hits DFCO timing will drop to 0 and injector pulse widths will also drop to zero. Once it crosses the lower threshold timing and fuel will resume
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Originally Posted by HumpinSS
Are you sure this isnt DFCO. while the car decels in gear and hits DFCO timing will drop to 0 and injector pulse widths will also drop to zero. Once it crosses the lower threshold timing and fuel will resume
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Originally Posted by HumpinSS
Well it takes a sec or two for it to enter so i doubt it is going in and out. A log will tell you better. It also goes in to OL when it does the DFCO thing, just an FYI
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Originally Posted by HumpinSS
No because the trims stop learning in open loop mode. and will populate with 0's if i am understanding your question correctly
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Originally Posted by gameover
timing ramps down before the injector cutout, you may not be reaching the injector cutout before DFCO disables and timing kicks up again.
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Aha. Now DCFO works again. I think I need to add a little more air in the throttle cracker tables now for my surging...it's a little better, but I still have a little bucking. I think it is better for the car to cruise a little than to buck like a bull...
