Hondata

Hello all,

I have been chasing a random 02a oxygen sensor code (1) since I've started my P28 s300 journey on a stock B16A2.

This code sets about every 5 to 10 miles and puts the car back in open loop. Up until the point the code is thrown, closed loop in my opinion reacts and tunes perfectly otherwise.

I have followed the forum advice. I initally wired the X-series wideband in d14 (without issues), and also now in D10 slot, with no change.

I have perfect feedback from the wideband working wonderful, gauge to ecu is perfect offset but seemingly have nagging issues with closed loop.

1) I have run full time closed loop, stock style closed loop to no avail.

2) D14 or D10.

3) Tried to set the switching timer to max value

4) Stock P30 cal setup for wideband input settings only and stock closed loop.

Any tips or feedback from others running into this issue? screenshots attached

Thanks

Post the calibration used and a datalog showing the issue

I'm not sure i can catch it in a datalog, as its at random at any point into a 15 minute datalog

here is the calibrations both used:

tune

and p30 b16 tester setup for wideband only as a sanity check

After lots of reading

it seems No AEM X series wideband works with S300, regardless of the timeout feature set to max. It simply isn't read the same 0-5v scale it's looking for

It appears the second the closed loop freezes and stop swinging, the code sets shortly after.

viewtopic.php?t=22105

Any feedback on this? PLX is 6-8 weeks out.

By no means a tuner but have same exact setup without issues. Aem x to d14, stock b16a2 in a ek sedan. Hondata seems to read up to 16.4-16.6 afr. Is the wire connected into the jumper harness?

When using any wideband it should be wired to D10. Using D10 requires the romoval of r136 and r138 on the board. Using D14 limits the upper and lower voltage so you won't see full range. Removing those resistors on D10 will give you full range. The only issue I have seen on the Xseries is the amount of time until you start getting voltage on the analog output. These are the settings I use with no issue.

catsman50 wrote: Mon Jun 16, 2025 11:39 am By no means a tuner but have same exact setup without issues. Aem x to d14, stock b16a2 in a ek sedan. Hondata seems to read up to 16.4-16.6 afr. Is the wire connected into the jumper harness?

which jumper harness are you referring too? do you have a picture of your closed loop settings?

TTR wrote: Mon Jun 16, 2025 1:16 pm When using any wideband it should be wired to D10. Using D10 requires the romoval of r136 and r138 on the board. Using D14 limits the upper and lower voltage so you won't see full range. Removing those resistors on D10 will give you full range. The only issue I have seen on the Xseries is the amount of time until you start getting voltage on the analog output. These are the settings I use with no issue.

hello, is this for your X series settings?

I've tried D10/D14 with no luck.

X series voltage seemingly has a much different voltage range then normal widebands and looks like it still falls within limits of R136/R138 as long as you set the activity (decel delay).

Most widebands are 0v=10 A/F 5v=20 A/F. Use the settings in the pics for the X series.

b_unit wrote: Mon Jun 16, 2025 2:15 pm

catsman50 wrote: Mon Jun 16, 2025 11:39 am By no means a tuner but have same exact setup without issues. Aem x to d14, stock b16a2 in a ek sedan. Hondata seems to read up to 16.4-16.6 afr. Is the wire connected into the jumper harness?

which jumper harness are you referring too? do you have a picture of your closed loop settings?

The obd2a to obd1 jumper harness I’m referring too. I wired into the jumper harness so I didn’t have to cut any of the stock harness on the car. It’s an Amazon special.

As for closed loop, I honestly haven’t played around close loop much. I run the car in open loop 99% of the time.

I do know my voltage to lamba is different than above. I’ll post a pic later today.