AEM UEGO Wideband acting funky...
#1
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AEM UEGO Wideband acting funky...
I don't understand this thing, since I got it the thing shoots back and forth constantly making a lightshow in my car. On the dyno the car is constant 11.5-11.6, doesn't move its great...I put the AEM sensor back in and take it for a stroll, start up it will go stupid lean then after itll warm up read perfect at idle(sometimes) other times it will be like OMG 15.6 then shoot down to _.__. I checked for exhaust leaks didn't hear anything. I have a cutout and i'm wondering if the position where its at is causing an issue, but closed or open the thing still is a mess.
Here is a picture of the cutout and its location, its now electronic and at the time the sensor bung was just sealed with an old O2 in the picture. 3in downpipe from turbo about 2 feet into the wideband then the cutout.
Here is a picture of the cutout and its location, its now electronic and at the time the sensor bung was just sealed with an old O2 in the picture. 3in downpipe from turbo about 2 feet into the wideband then the cutout.
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when cruising does it stay around 14.7-15.1? Your computer is continually adjusting the A/F going from slightly lean to slightly rich, don't be concerned with the lean start up it's my understanding that it's the wideband warming up.
All that bouncing around is actually what's going on with your fuel mixture, when idling or cruising your pcm is making all those adjustments. Same with coasting the mixture gets goofy especially if it's been tuned. If it stays between 14.7-15.1 when cruising and richens up when under hard acceleration I think it's working correctly.
All that bouncing around is actually what's going on with your fuel mixture, when idling or cruising your pcm is making all those adjustments. Same with coasting the mixture gets goofy especially if it's been tuned. If it stays between 14.7-15.1 when cruising and richens up when under hard acceleration I think it's working correctly.
#4
That sounds absolutely normal. I see you have no cats, but if you left the air pump on in the tune, then the AFR will read lean on start up. The air pump flows cool fresh air to the cats to help run them lean to warm them up quicker. As for driving around, if you are tuned in closed loop the ECM will bounce around the AFR from lean to rich. This is the only way the ECM can determine if the AFR is at the desired level. The ECM tries to swing around 500mV on the narrow bands. Also when you are decelerating, the ECM will kick into DFCO (Deceleration Fuel Cut Off) mode, and this can look super lean to a wideband, but it helps fuel economy and doesn't hurt the engine as spark is reduce to zero as well under this condition.
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That sounds absolutely normal. I see you have no cats, but if you left the air pump on in the tune, then the AFR will read lean on start up. The air pump flows cool fresh air to the cats to help run them lean to warm them up quicker. As for driving around, if you are tuned in closed loop the ECM will bounce around the AFR from lean to rich. This is the only way the ECM can determine if the AFR is at the desired level. The ECM tries to swing around 500mV on the narrow bands. Also when you are decelerating, the ECM will kick into DFCO (Deceleration Fuel Cut Off) mode, and this can look super lean to a wideband, but it helps fuel economy and doesn't hurt the engine as spark is reduce to zero as well under this condition.
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Me neither, I always thought it was the heater circuit in the wide band. So does the air pump stay on until it goes closed loop? Also is that the only purpose of the air pump?
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The airpump is out and holes are plugged, I'll check with my tuner tomorrow to see if its off in the tune..the thing freaks me out because as i'm driving its never balanced lol. I know about DFCO, my wideband reads around 10-11.5 during that, so I don't know what the deal is..on the computer though it reads 11.5-11.6 consistent the entire time.
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#8
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The airpump is out and holes are plugged, I'll check with my tuner tomorrow to see if its off in the tune..the thing freaks me out because as i'm driving its never balanced lol. I know about DFCO, my wideband reads around 10-11.5 during that, so I don't know what the deal is..on the computer though it reads 11.5-11.6 consistent the entire time.
Its not the wideband, ITS THE TUNE.