Another Faulty O2 Sensor?
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Joined: Jan 2004
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From: Portland, OR
Another Faulty O2 Sensor?
Hey Guys,
So I just replaced an o2 sensor that would not calibrate. I used the same Bosch LSU4 sensor (5 wire) that comes with the tuner. Everything came up great in the free air calibration (263 was the value) but when I go logging it does something very strange.
At around 5k, under load so 3rd gear or higher, the AFR's will go from being 11s to >25:1 in the logs. Its like the o2 sensor quits working. I put the o2 sensor in the down pipe close to the front of the CAT. The o2 sensor will complete Free air calibration without any issues but I cant get good AFR readings above 5k. Under 5k everthing looks like I would expect it. 14.7:1 at idle and cruise etc.
Any ideas?
So I just replaced an o2 sensor that would not calibrate. I used the same Bosch LSU4 sensor (5 wire) that comes with the tuner. Everything came up great in the free air calibration (263 was the value) but when I go logging it does something very strange.
At around 5k, under load so 3rd gear or higher, the AFR's will go from being 11s to >25:1 in the logs. Its like the o2 sensor quits working. I put the o2 sensor in the down pipe close to the front of the CAT. The o2 sensor will complete Free air calibration without any issues but I cant get good AFR readings above 5k. Under 5k everthing looks like I would expect it. 14.7:1 at idle and cruise etc.
Any ideas?
