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I searched in the help files and on the forum but did not see any info on this. Which value is the actual AFR ratio reading from the wideband and what is the other parameter telling me?

AFR is what to watch on RSX/swap. Some vehicle sensors read richer than they should.

KTuner wrote:AFR is what to watch on RSX/swap. Some vehicle sensors read richer than they should.

Thank you for the heads up on the sensor readings. I'll comp pair to a known good wide-band. So what is the afradj reading?

Adjusted for those models that read rich.

KTuner wrote:Adjusted for those models that read rich.

Sorry but this is just an absolutely terrible/lazy explanation of what this channel is.

Lambda sensors are greatly affected by the pressure of the environment they're in. On turbo cars, this is why the sensor should always be located after the turbo. However, on some OEM turbo applications (Honda 1.5T for example) the sensor is located pre-turbo, to allow it to read and respond as quickly as possible, meaning it's now exposed to very high exhaust backpressure when in boost. In order to get an accurate reading from the sensor, exhaust backpressure must be measured (or calculated by a model) which is then used to "correct" the reading from the sensor. This is why AFR and AFR.ADJ read the same when at light load. Under load, AFR is the reading from the sensor, and AFR.ADJ is backpressure compensated. Therefore, AFR.ADJ is more of a "true" reading.

What I don't know is if the backpressure calculation model is extrapolated to boost levels (and therefor backpressure levels) higher than factory boost pressure.

bbrtuning wrote:

KTuner wrote:Adjusted for those models that read rich.

Sorry but this is just an absolutely terrible/lazy explanation of what this channel is.

Lambda sensors are greatly affected by the pressure of the environment they're in. On turbo cars, this is why the sensor should always be located after the turbo. However, on some OEM turbo applications (Honda 1.5T for example) the sensor is located pre-turbo, to allow it to read and respond as quickly as possible, meaning it's now exposed to very high exhaust backpressure when in boost. In order to get an accurate reading from the sensor, exhaust backpressure must be measured (or calculated by a model) which is then used to "correct" the reading from the sensor. This is why AFR and AFR.ADJ read the same when at light load. Under load, AFR is the reading from the sensor, and AFR.ADJ is backpressure compensated. Therefore, AFR.ADJ is more of a "true" reading.

What I don't know is if the backpressure calculation model is extrapolated to boost levels (and therefor backpressure levels) higher than factory boost pressure.

Actually, AFR.Adj was added for older platforms that have O2 readings change over time, not the 1.5T platforms, and the OP has an RSX/Swap application, hence the original response to that effect. It is not a back-pressure compensated reading. It's not data from the ECU at all, but rather a calculated compensation for the aforementioned situation based on years of collective data.