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JesterX18 · 08-18-2014, 05:37 PM

So I've been switching ECU's back and forth and seemed to have it idling around 15.7 with my friends ECU. Its not misfiring and comes down to idle perfect. What I notice is that my lean condition is in direct relation with my o2 sensor reading via datascan. when the o2 reads 87 at idle its running good. if I blip the throttle the o2 reads 0 for ten seconds or so and then goes back to reading 87. While it reads 0 the AF ratio is lean on the wideband. While driving the o2 switches back and forth normally. When I plug my ECU in the o2 always reads 0 at idle and wont change unless I drive it and accelrate. And my wideband is constanlty lean at idle. Also it stumbles coming down from decel. So then I decided to unplug it. The o2 sensor now reads 32 and still runs like crap. So all ive done is switch ECU's and at least when its warm the problem seems to be gone, except when the o2 reads 0 after I rev it. So it seems this ECU is bad. Another thing to note is my ECU is tuned fro 720cc injectors as that's what they flow tested at wolfes and my friends for 810cc. so my friends ECU tends to run leaner across the board. 14.1 AFR in boost in my car. I have read the o2 reading should be zero at idle.... is this true?

08-18-2014, 05:37 PM	#2
JesterX18 Join Date: Feb 2013 Location: Clifton Park, NY Age: 32 Posts: 34 Trader Rating: (2)	update So I've been switching ECU's back and forth and seemed to have it idling around 15.7 with my friends ECU. Its not misfiring and comes down to idle perfect. What I notice is that my lean condition is in direct relation with my o2 sensor reading via datascan. when the o2 reads 87 at idle its running good. if I blip the throttle the o2 reads 0 for ten seconds or so and then goes back to reading 87. While it reads 0 the AF ratio is lean on the wideband. While driving the o2 switches back and forth normally. When I plug my ECU in the o2 always reads 0 at idle and wont change unless I drive it and accelrate. And my wideband is constanlty lean at idle. Also it stumbles coming down from decel. So then I decided to unplug it. The o2 sensor now reads 32 and still runs like crap. So all ive done is switch ECU's and at least when its warm the problem seems to be gone, except when the o2 reads 0 after I rev it. So it seems this ECU is bad. Another thing to note is my ECU is tuned fro 720cc injectors as that's what they flow tested at wolfes and my friends for 810cc. so my friends ECU tends to run leaner across the board. 14.1 AFR in boost in my car. I have read the o2 reading should be zero at idle.... is this true?