So I just installed a AEM Wideband with the UEGO sensor. When I turn the key the gauge goes to normal range and the sensor warms normally, I start the car and it will read for about 3 seconds and then max out all the way to the lean side and it will just show 3 dashes. It doesnt the exact same thing when I am cruising at the same speed/RPM on the road. When I accelerate it works perfectly normal. What would be causing this? I know my car runs really rich so I would understand if it maxed out to the rich side but the lean side makes no sense to me. I have the UEGO sensor installed before the CAT, roughly 45" from exhaust port cylinder 1. Would it be too far away? Thanks.
instructions say at least 18" downstream. it it installed in the downpipe? perhaps it is too far, but then again some dyno shops use tailpipe o2 sensors. maybe there is an exhaust leak before the sensor.
It said for turbo cars it should be at least 36" bc of heat and im turboing my car shortly. My manifold is 4-2-1 and its about 4" after where it goes into 1. Maybe its an exhaust leak then
So I searched my exhaust and found 2 small leaks, got those fixed and it still does the same thing. Any other thoughts? Thanks.
did you buy it new? how do you know your car runs rich with low load?
Well I just put in 350cc injectors with no tune while I wait for a few more parts for my turbo and then when the turbo is on I will get it tuned. And yes bought it new, never dropped the sensor or anything like that. My thoughts is it cant be wiring or the sensor bc it does read while accelerating. If it were the sensor or wiring it wouldnt work at all correct?
It’s probably not the wiring or the sensor distance. the distance isn’t an exact science to make it work and the wiring is pretty straight forward. Is this on KA? You might be washing the cylinders with unburnt fuel but those arn’t very big injectors. can you put your stock injectors back in to and see how the sensor is working then?
If you put in oversize injectors the ecu might be cutting back duty cycle when it runs naturally rich from the oversize. It’s possible you’re actually running lean.