Running closed loop with a 0-5v wideband input.

shawn934 · Post by **shawn934** » Wed Dec 02, 2009 9:22 pm

So in s300, I'm wondering why running closed loop with a wideband is a bad idea, I mean using the 0-5v output and setting a target voltage of 2.37v.

How does hondata choose the appropriate % fuel change with a narrow band?

Since in a lean or rich condition with a narrorband, the voltage changes much more slowly than the AFR. So i'm assuming it won't use %change in voltage since that wouldn't work very well...

Is it an iterative process until it hits the target?

Fill me in!

Thanks

Shawn

kelly · Post by **kelly** » Thu Dec 03, 2009 2:40 pm

Most widebands send out a voltage that is backwards from what the ECU expects to see. Wideband is low voltage=rich, high voltage=lean. Narrowband is the opposite.

That being said, I use NepTune which can invert and use a wideband for closed loop and found that narrowband emulation works better.

The ECU expects to see a sharp transition and works better when it gets one.

shawn934 · Post by **shawn934** » Thu Dec 03, 2009 6:08 pm

Right. I didn't think of that, good call.

kinetics · Post by **kinetics** » Fri Dec 04, 2009 12:45 pm

If you're using a PLX wideband setup, it won't matter, since it can feed both WB and NB correctly, and the S300 has no trouble reading both.

Post by **Spunkster** » Mon Dec 07, 2009 12:40 pm

You can only run closed loop with a narrow band signal. You cannut input a 0-5V wideband signal to run closed loop as it will not work correctly. For this reason we recommend the PLX Devices widebands and they have both narrowband and wideband outputs at the same time, this allows you to datalog the wideband signal and run closed loop from the narrowband signal.