Quoting Blown1:
So theoretically if you were going to move it where would you move it to?????
I wouldn't. Its very tough to find a spot for the bung and O2 to clear. As I said, just ignore it at idle.
Quoting Blown1:
the only thing I have done is back the biss screw out a bit.
If the ISC step is already at zero, you don't want to back the screw out even further, that will cause idle surge issues. You want to turn it in until you see 5-10 steps at idle at most, IMO.
Quoting Blown1:
Just need the damn afpr so I can figure out why its so lean at idle yet so rich at WOT.
BTW, I don't consider 10.8:1 to be "so rich" when the openloop map targets are set to 11.0:1. That 0.2 difference is so small as to be almost insignificant, and probably much less than the accuracy of your wideband. There are way too many things that could easily add up to throw off the AFR by 0.2, like injectors that flow slightly more, fuel pressure being 1 psi too high, MAS calibration, type of air filter used, etc. That is why the factory builds in the fueltrims, to compensate for parts that are at both extremes of the manufacturing tolerances, aging, and wear of components. But, the fueltrims don't work in openloop, and it can be a little trickier to hit the desired AFR, so the factory over compensates by making the openloop maps a very rich 9.5:1. Of course, they also do this to keep the combustion chambers cooler and reduce knock, but it is highly inefficient.
So theoretically if you were going to move it where would you move it to?????
I wouldn't. Its very tough to find a spot for the bung and O2 to clear. As I said, just ignore it at idle.
Quoting Blown1:
the only thing I have done is back the biss screw out a bit.
If the ISC step is already at zero, you don't want to back the screw out even further, that will cause idle surge issues. You want to turn it in until you see 5-10 steps at idle at most, IMO.
Quoting Blown1:
Just need the damn afpr so I can figure out why its so lean at idle yet so rich at WOT.
BTW, I don't consider 10.8:1 to be "so rich" when the openloop map targets are set to 11.0:1. That 0.2 difference is so small as to be almost insignificant, and probably much less than the accuracy of your wideband. There are way too many things that could easily add up to throw off the AFR by 0.2, like injectors that flow slightly more, fuel pressure being 1 psi too high, MAS calibration, type of air filter used, etc. That is why the factory builds in the fueltrims, to compensate for parts that are at both extremes of the manufacturing tolerances, aging, and wear of components. But, the fueltrims don't work in openloop, and it can be a little trickier to hit the desired AFR, so the factory over compensates by making the openloop maps a very rich 9.5:1. Of course, they also do this to keep the combustion chambers cooler and reduce knock, but it is highly inefficient.
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