17 SS Flex Fuel Tuning Q

[VoidTuning]

Hi All,

Currently tuning my 17 SS on flex fuel. Sensor and everything else is working correctly. I do not currently have a wideband and I was wondering how I can verify the car is not leaning out on e85? I have a 17 WRX on e85, that car has an OEM wideband that Cobb is able to monitor. Do the 17's have this also since they are DI?

Also, what DTC's must be turned off for flex fuel?

Thanks,

[5FDP]

No wideband, no way of knowing real time air fuel ratio or lambda.

These vehicles do not run OEM wideband sensors. You need to install one in the exhaust or be on a dyno with a wideband.


Why would anything have to be turned off for adding a flex fuel sensor?

If you setup the sensor in the calibration it should run as if it was a factory installed part and function with all the flex fuel tables as if it were factory.

[veee8]

You will want to enable the flex fuel sensor diagnostics, under the fuel tab, and also the DTC's for the sensor.

[VoidTuning]

No wideband, no way of knowing real time air fuel ratio or lambda.

These vehicles do not run OEM wideband sensors. You need to install one in the exhaust or be on a dyno with a wideband.


Why would anything have to be turned off for adding a flex fuel sensor?

If you setup the sensor in the calibration it should run as if it was a factory installed part and function with all the flex fuel tables as if it were factory.

I'm just speaking from experience. E85 for my WRX had to turn off over 10 DTC codes as per instructions from the Cobb guide, these includes DTC for lean, rich, o2 sensor slow response, etc.

[VoidTuning]

You will want to enable the flex fuel sensor diagnostics, under the fuel tab, and also the DTC's for the sensor.

Awesome thanks for the info. Do you know what DTC # I specifically need to turn on?
Thanks,

[veee8]

PO178 and PO179

[Hyperlinkblue]

PO178 and PO179

Hmm mine are not turned on, maybe i should do that. I wonder if it would actually work or not because the way i picture it, that would be for a true flex fuel vehicle where it has its own harness/wiring from pdm/pcm or where ever it gets power from. That way if there is a short or a open it will report it. My sensor piggy backs off the EVAP solenoid.... so if something grounded out it would probably show up in that circuit. Then there is the signal wire going into the ecm so the second idea would be that being OORL or OORH?

[veee8]

The diagnostics are for the flex fuel sensor circuit. You want them enabled and working, even when using evap or coil etc for the power source. I've seen so many setups where they were not turned on, and there was a problem with the wiring, and you wouldn't even know. Most default to 40% alcohol when there is a problem.

[Hyperlinkblue]

The diagnostics are for the flex fuel sensor circuit. You want them enabled and working, even when using evap or coil etc for the power source. I've seen so many setups where they were not turned on, and there was a problem with the wiring, and you wouldn't even know. Most default to 40% alcohol when there is a problem.

thanks for posting back, i turned mine on and will see how it goes on my next update

[VoidTuning]

The diagnostics are for the flex fuel sensor circuit. You want them enabled and working, even when using evap or coil etc for the power source. I've seen so many setups where they were not turned on, and there was a problem with the wiring, and you wouldn't even know. Most default to 40% alcohol when there is a problem.

Thanks for all the help. Customer got a wideband on the car, got everything running extremely well. Running MAF only with LTFT disabled.