PLX wideband interaction with Hondata questions?

[itr206]

I just got a PLX M300 today to use for my tuning. I understand how to get everything working except for the wideband/narrowband outputs?
I removed my stock o2 and was planning to not only use this for tuning, but for permanent use in the car as a reliable way to see if for some reason my tune changes or if i need to make changes as time goes on .

Now what i got from PLX told me i would use the Wideband outputs for tuning when im in Open loop mode.

Then when i put it into closed loop i would be using the narrow band output.

My question is would i then need to keep my map in open loop to read the wideband readinngs all the time? If i put it in closed loop when im done woldnt it just give me the same effect as getting the same scewed readings from the stock 02 sensor?
Im just looking for a way i can reliably use my wideband in an every driving occasion experience for added piece of mind.

thanks for the help

[DaX]

Not 100% sure this is correct, but this is how I understand it:

My question is would i then need to keep my map in open loop to read the wideband readinngs all the time?

Wide band output can only be used in open loop.

You use narrow band output for everyday driving which should be done in closed loop.

If i put it in closed loop when im done woldnt it just give me the same effect as getting the same scewed readings from the stock 02 sensor?

I don't know about screwed up readings, but yes, it will be the same as readings obtained from your stock o2 sensor, i.e. - you won't be seeing large changes in your air/fuel ratio because it is using the narrow band sweep across stoich.

[itr206]

ok thats how i was understanding it too . are there any adverse affects from not putting the map back in closed loop other than economy?

I was told once that if the tune was done correctly closed loop really shouldnt be needed to make the changes because it will be dead on? correct?
the car doesnt get driven that much , but when i do i wann make sure i can keep an eye on whats going on .


actually now that i think of it . would it be best to keep it in closed loop when done and set it that at a certain mbar to switch back into open loop? that way closed loop does what it needs to in the partial maps and then WOT it switches to closed loop to give me the info i need?
then again though i dont think i will get the correct readings dead on at partial throttle i guess?

[Jaker]

The PLX display will show you wide band no matter which one is connected to the ECU. The Hondalogger will show whatever is connected to the ECU.

So as long as you don't need to datalog the output, and you're happy watching the display when not tuning, you can easily use the narrow band output of the PLX for day to day driving.

[itr206]

that answers alot, thanks. thats what i weas looking for

so realistically i can leavethe PLX wired in wideband mode all the time and set the Hondata to do its closed under 650mbar and open above that , the PLX will read correcly both ways, but the Hondalogger will only read correctly when in open loop.

[jpilcher]

You can set the load value for when the ecu switches over from closed loop to open loop. This means that you can keep it in closed loop and get good gas mileage, then when you floor it the ecu will jump to open loop and use the open loop maps.

[Jaker]

that answers alot, thanks. thats what i weas looking for

so realistically i can leavethe PLX wired in wideband mode all the time and set the Hondata to do its closed under 650mbar and open above that , the PLX will read correcly both ways, but the Hondalogger will only read correctly when in open loop.

When you drive on the street, and are not doing any tuning, to assure the best fuel economy, it is necessary to connect the narrow band output (grey wire) to the ECU and turn on the O2 sensor in Hondata RomEditor.

The PLX display will still show wideband mixtures, but the ECU needs to see narrowband signals for the economy and emissions to be reasonable.