Hondata

So I recently put my car back on the dyno to freshen up the tune after making some minor setup changes. Of course I hadn't opened Smanager in a few months, so I needed to update the software to v2.6.7. On the dyno I was getting very rare misfires, usually only shortly before the end of the pull which was 7200rpm. My rev limiter was set to 7600, so I raised it to 8k, and it still would misfire around 7000-7100. Only happened about once every 3 or 4 pulls. After dyno tuning was done, I went on the street to fine tune fueling in real world conditions, and it started misfiring on rare random occasions all all different rpms and manifold pressures; cruising, light acceleration, heavy acceleration, and wot. I replaced the plugs, wires, cap, and rotor and tried again. Same thing, random rare misfires at various rpms and loads, typically only in fourth gear, but occasionally third and fifth gear too.

I recorded multiple datalogs and checked almost all of the parameters, and nothing stood out as odd. Until I decided to check GEAR, and sure enough, the logged gear is spiking every time there's a misfire. Prior to updating the software, the car has never misfired, and I checked old logs and there has never been spikes in the logged gear. My gear ratios are set perfectly to what they actually are, same for final drive, and I have never altered these ratios.

Attached is a datalog and my tune from a fourth gear pull I did on the highway tonight, with multiple rapid misfires all at the same exact time the log shows the gear spiking from 4th to 5th and back to 4th again. (The tires did spin once I reached peak torque area, hence the rapid rpm increase)
Any advice on how to fix this?

I fixed it, the WRONG way. I set fourth and fifth gear ratios in the tune to much lower numbers than their true ratios. I lowered them gradually, doing pulls and datalogs each time I made a change to see if it was still doing it. The following was what I ended up with in order to prevent this glitch until it gets fixed in the software:
3rd: actual: 1.269 - kept the same
4th: actual: 0.967 - changed to 0.930
5th: actual: 0.812 - changed to 0.760

I know my ratios are the actual above, because I've counted the teeth on all gears including final drive gears on multiple occasions.
I shouldn't have to enter wrong values for it to work properly. This has never been a problem until the most recent update.

Side note: even though none of my datalogs show any issues with the VSS, I tried two other known good vss's just to make sure, and it didn't affect anything.

We are not aware of anyone else having an issue like this. Unless we can reproduce it here there isn't anything that we can change. Can you provide any calibrations and datalogs prior to this showing it working correctly?

Spunkster wrote: Fri Nov 16, 2018 5:46 pm We are not aware of anyone else having an issue like this. Unless we can reproduce it here there isn't anything that we can change. Can you provide any calibrations and datalogs prior to this showing it working correctly?

of course. these are all from september-october 2017