Diagnosing AFR Issue
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Diagnosing AFR Issue
So to keep things simple and to the point I have an AFR issue only related to light throttle. AFR either goes pig rich or stupid lean 11afr or 17afr on light throttle.. Always a toss up and its one or the other. By monitoring dashhawk I noticed that without the issue happening the primary O2 sensor will read anywhere between 700mv-800mv. However, when the AFR freaks out the sensor will be reading very very low. Anywhere between 15mv-70mv which I imagine is a dead sensor. I'm not about to throw parts at the car unless I'm sure it's the issue. The car is maintained and other sensors such as the MAF are spotless.
Other odd note: doesn't happen above 46mph.
Also, does anyone know if on the bottom right corner of my Dashhawk means 'C' for Closed Loop and 'O' for Open Loop? Can't seem to find that answer anywhere. Even on MSD's website lol. Nor the manual.
Other odd note: doesn't happen above 46mph.
Also, does anyone know if on the bottom right corner of my Dashhawk means 'C' for Closed Loop and 'O' for Open Loop? Can't seem to find that answer anywhere. Even on MSD's website lol. Nor the manual.
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I saw 3 different commanded AFR #'s. The standard 14.7 which is normal. But it would either jump to 13.5 or 16.5 commanded randomly for some time. All at cruise under light throttle.
#9
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if for some reason your are hitting enough pressure from the turbo to trigger pe mode in your tune....which would make it go from closed loop to open loop......COT settings could change commaded fuel....
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Wouldn't know as I do not have HP Tuners. Just gonna take it up with my tuner. No worries.
Last edited by Mindrot; 03-16-2013 at 03:44 PM. Reason: Automerged Doublepost
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if the kpa trigger is set too low it will do this. {pe trigger} or the tps trigger is set wrong. set the cat test and rear o2 test to disable, and set the cot temps to stock, but disable the activity of it.
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