Thread: Tuning for Gas Mileage

Dude your awesome! Thanks!

Disabled the Front O2 sensor yesterday. The check engine with P0130 came up in no time.

I was able to lean out the cruising to 16's. When I would go WOT, it would be below 12's, so that was fine. Until I tried going mid throttle in 5th gear and starting to build boost. The A/F would be again in 16's at 3-4 psi, map trace showed me being in a 50 TP, which has fuel for 13 AFR. There is no simple way to get around this. This just shows why the O2 sensor cannot simply be disabled.

Is it possible to disable O2 feedback only for certain cells? I only care about 2800-3600 RPM up to 50 TP.

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Now onto Timing tuning for gas mileage, having higher timing for the same mixture will mean a more complete burn, thus a higher AFR right? Thus the ECU would try to compensate for the higher AFR's and add more fuel to lower the AFR right?

What would the value be or equavalent for the B13 ecu at 038?
Currently, I have it at F5.

both enabled=?
both disabled=?
02 disabled=?
knock disabled=?

Thanks

B13 is the same.

That is interesting because I have looked at a lot bins and they mostly have F5,F0,B4, or 00, but never the values you have given.

Could you translate the above values? If it's confidential I understand.

The values above are in hex and are for a stock 1M861 bin with manual trans and EGR enabled. It gets rather complicated and requires understanding hex and bit masks, and there is intellectual value in knowing what all 8 bits mean. From what I've shown above, you can figure out which bits enable O2 and knock, which is the original question I was trying to answer.

Dave

Any ideas on how to make the oxygen sensor be ignored only in a specific part of the map? I got a long trip coming up again, would like to get better gas mileage then 28mpg hehe.

Not yet, in a B14 anyway. It may be possible, I just don't know enough about the B14 code yet to tell.

I already have a way to use WBO2 0-5V output to tune in closed loop working on a S13 SR20DET, so hopefully I can implement it in the B14 code also.

Dave

Well that's a shame, what I did notice though is if I change the value from 14.7 to something lower, it will no longer be in closed loop. Unfortunately doesn't work the other way around hehe.

How can you tell if it's in closed loop or not?