Closed Loop Malfunction

[B16Matt]

Thanks mate, really appreciate it

In that case, will do further testing with a P72/P75 and see what we find!

[1 bad em1]

Had this same issue happen to me now a couple of times and found these posts about it like others have, same issue as others have mentioned … closed loop stops working on decel and s. trim becomes stuck at whatever value it happened to be at, won’t come back on until car is shut off/back on.

AEM x-series 4.9LSU wired to D14 (others have had issues with D10 etc. so don’t think that’s the problem since D14 reads enough voltage to go from like 9-16 afr with the 4.9 sensor which is plenty of range to tune). Reading other posts I’m thinking it is something to do with the software thinking that the wideband is no longer reading properly and disabling closed loop.

We need a fix for this that isn’t just “buy a different wideband” aka a cop-out solution. Please fix the software so that it goes back into closed loop … lots of people use this wideband and many are having the same issue regardless of which pin it is on. If you think it is because the x series only goes to 18afr which triggers the disabling event then modify the software so it doesn’t trigger in that scenario or increase the timer before it triggers or something?

[Hondata]

Apologies, we will look in to this.

[B16Matt]

I agree with ‘1 Bad Em1’, this is absolutely a product or software issue. Multiple different setups over the years, multiple different ECU boards and scenarios, the same results occur. All the different variables have been changed and thought of. There’s gotta be some sort of fix for this that can be done via a future update, otherwise i can’t see there being another solution for this. It’s definitely a pretty major/important issue too, cause at the end of the day we can’t use the ECU properly/how we want to… I hope to hear good news soon!

[Spunkster]

Have you tried not using D14 and use D10 instead so that the full voltage range can be read?

[Hondata]

The ECU wants to see a rich to lean or lean to rich swing every 30 seconds or so, not including during overrun. If you limit the short term trim to say +-10% but the engine requires +12% trim, then it will not see the swing and will deem that closed loop is not working. ECU doesn't bother to generate a code; you'd have to ask Honda why not.

I've exposed the timeout (default 29.5 seconds) which can be increased to 10 minutes or so. That should take care of it.

https:\\hondata.com\updates\SManagerV2-8-8.exe

[B16Matt]

Awesome, Thankyou guys! Will experiment and report back

[1 bad em1]

The ECU wants to see a rich to lean or lean to rich swing every 30 seconds or so, not including during overrun. If you limit the short term trim to say +-10% but the engine requires +12% trim, then it will not see the swing and will deem that closed loop is not working. ECU doesn't bother to generate a code; you'd have to ask Honda why not.

I've exposed the timeout (default 29.5 seconds) which can be increased to 10 minutes or so. That should take care of it.

https:\\hondata.com\updates\SManagerV2-8-8.exe

I just saw this comment now, I asked about this in the v2.8.8 thread twice thinking this was what the update was for and I'm super excited that it is an attempt to solve this problem (hopefully for good).

Now if we could get some kind of fix for the "hot restart lean" issue that would pretty much solve all the problems I have had with the s300. We need some way to add 10-15% ish fuel but only after a hot restart and be able to set the duration or just have it go for 15-30 seconds until closed loop can take over and start compensating.