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Oxygen sensor 2

  • Fox.b
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7 years 8 months ago #20560 by Fox.b
Oxygen sensor 2 was created by Fox.b
My understanding of the downstream o2 sensor is that it should read above 450mv(rich) when in closed loop, engine warm and ST and IT fuel trims are reading ok (around 0%).
I have just started looking at engine data and seen a couple of cars whet the trims are both around zero%, o2 sensor 1 is fluctuating above and below 450mv but the o2 sensor 2 is fixed lean (below 450mv). If I floor the throttle the o2 sensor 2 goes rich so I know it is working.

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