Commanded AFR in closed loop = 13.8? Is this normal?

[gone.a]

^ For the most part in open loop, Ya. But I have seen some readers display the "Target AFR" from the fuel map (by target afr I mean the current fuel map setting or digit). Just curious what his tool is trying to show. A reading from the narrow band sensor, or some sort of PID information from the ECU.

I am using an ELM327 device that plugs into the obd2 port and reports via bluetooth to an app I have on my phone. It reports many parameters such as commanded AFR, measured AFR, long and short fuel trims, coolant temp, as well as o2 sensor voltage.

Other than what I see reported on the screen of my phone I have no clue as to where the actual numbers come from.

I assume the commanded AFR is reported from the ECU somewhere, and the measured AFR is deduced from O2 sensor voltage but I have no idea.

The numbers reported on my app are close to stoich for CA E10 fuel, so I would be inclined to trust them.



Side note - At wide open throttle on 87 octane CA fuel, and at higher RPM, timing gets down to about 11 degrees which seems fairly retarded.

[live4redline]

If the measured AFR is a voltage then I agree.

Also, tuned timing typically advances to peak horsepower and then starts to retard toward redline.

Timing Example... 7 8 9 10 11 12 13 14 *Peak 15* 14 13 12 11 *Redline*

[gone.a]

Your reading the 13.8 off a factory O2 sensor? Might need to check if the sensor being read is a narrow or wide range sensor also. It may be a narrow band and the reading is being rounded to number for display purposes. I don't know of any Mitsubishi's that have wide band sensors from the factory but I also haven't looked into the Mirages sensor. Also to note, Mitsubishi tuning doesn't work on a 1:1 AFR setting either. This mostly applies too the closed loop tuning but for example the fuel map may say 12afr at 4000rpm and 75load and the actual AFR on a wideband sensor will read 14.5afr. It's confusing to understand at first but that's just how Mitsubishi does it. I'm not familiar with the tool your using but you may be seeing what the ECU map is trying to do instead of the actual reading and if that's the case... Trying to do 13.8afr could easily translate to an actual 14.5afr.

Looks like our upstream o2 sensor is wideband....stock.

[fletcherkk@gmail.com]

Can someone tell me if the 2017 o2 sensors are narrow or wideband? I also have installed the headers from Speedlab and both sensors have triggered a service engine, would like to test the MAGNUM O2 Sensor Simulator but unsure which simulator to purchase.

[inuvik]

Can someone tell me if the 2017 o2 sensors are narrow or wideband? I also have installed the headers from Speedlab and both sensors have triggered a service engine, would like to test the MAGNUM O2 Sensor Simulator but unsure which simulator to purchase.

Doesn't the Speedlab Header have their O2 sensors located incorrectly (on a single cylinder's exhaust vs the OEM's all 3)?

[fletcherkk@gmail.com]

inuvik, I'm not aware of the HotPipes headers having o2 locations in wrong place (but i'm sure its possible). I have 2 codes being displayed:
P0137-Sensor Low voltage Bank1 Sensor2
P0031-Oxygen Sensor Heater Control Circuit Low Bank1 Sensor1

I'm trying to find out if the o2 sensor is wide or narrow so I can try the Magnum Tuning simulator. My current voltage reading on o2 is 1.2v but I've been told that this could be a defective 3-Volt wideband sensor that delivers low voltage (lean signal) and ECU delivers more fuel to the chambers constantly.

[MightyMirageMpg]

The sensor isn't faulty.

There's 2 sensors and one (closer to engine) is called a linear afr sensor. The rear is a heated sensor.

I think you need to buy defoulers and trick the ecu

[gone.a]

Non OEM replacement sensors indicate that the rear o2 sensor is a narrow band heated type. The repair manual also calls it a heated 02 sensor. I tried running a defouler on the rear o2 but ran into significant clearance issues with the stock exhaust. Not sure if that would be the case with aftermarket headers though.

Note - I posted about this previously and incorrectly stated we had a rear wideband.

[shepd]

The 555 timer circuit should work for a narrow band sensor emulator:

http://www.chippernut.com/blog/o2-simulator

Leave the heater portion hooked up to the O2 sensor.