Open Loop/closed loop question....
01-25-2002, 01:14 PM
#1
Open Loop/closed loop question....
Ok, so here goes
I remember reading a post not too long ago about how a 4th gen runs in closed loop mode when cold, meaning the ECU pays no attention to sensors/reading etc, and in open loop uses all sensors etc, so my question is,why do I get stuttering/hesitaion before 3500 rpms, and then again at the end of 2nd gear @ ~ 5000-5500rpms, but when cold, at times I do not get the stuttering at all, and sometimes its worse when closed loop than open, so if the ECU pays no attention to sensors then obviously the sensors are not what's wrong, so what else could be the problem? I thought maybe a bad MAF, but that plays a role with the O2 sensors, right? Maybe the injectors need cleaning, because when in closed loop, air/fuel mix is a little more rich, hence no hesitation.
Another pondering thought for some of us to think about. Would it be smarter to start a race part throttle(til ~3500rpms) , because it is also said that when at part throttle, ECU is in closed loop, It makes sense, because haven't you ever taken off from a dead stop and felt better pull at part throttle than full? So maybe part throttle it til 3500, then floor it? Because when you part throttle it, it feels stronger up to whatever % throttle you're opened at, meaning if you're at 60% throttle, it will pull harder than it does @ 100% throttle but only up to 60%, then at 60%, open it up all the way?
thnx nmexmax
I remember reading a post not too long ago about how a 4th gen runs in closed loop mode when cold, meaning the ECU pays no attention to sensors/reading etc, and in open loop uses all sensors etc, so my question is,why do I get stuttering/hesitaion before 3500 rpms, and then again at the end of 2nd gear @ ~ 5000-5500rpms, but when cold, at times I do not get the stuttering at all, and sometimes its worse when closed loop than open, so if the ECU pays no attention to sensors then obviously the sensors are not what's wrong, so what else could be the problem? I thought maybe a bad MAF, but that plays a role with the O2 sensors, right? Maybe the injectors need cleaning, because when in closed loop, air/fuel mix is a little more rich, hence no hesitation.
Another pondering thought for some of us to think about. Would it be smarter to start a race part throttle(til ~3500rpms) , because it is also said that when at part throttle, ECU is in closed loop, It makes sense, because haven't you ever taken off from a dead stop and felt better pull at part throttle than full? So maybe part throttle it til 3500, then floor it? Because when you part throttle it, it feels stronger up to whatever % throttle you're opened at, meaning if you're at 60% throttle, it will pull harder than it does @ 100% throttle but only up to 60%, then at 60%, open it up all the way?
thnx nmexmax
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