ccsfd

Got an MS2E, on my 99 with FM 2560 kit. Iv spent a few days getting my tune to where it is and its been running great for the last couple weeks driven everyday,then suddenly without any changes to the settings everything turns very rich. This happened once before and I posted about it here:

https://www.miataturbo.net/megasquir...ry-rich-72067/

and now its happened again. exactly the same problem, car running over rich
out of the blue. Any ideas what may cause this?

coldstartAE3lean.msq

different msq to the above link but exactly the same rich afrs idling @ 10s-11s when it was idling at 13s for two weeks. And its not just the idle, the whole map gone rich. Fuel economy was great last week now its crap and all on the same settings. Its not the wideband, last time I calibrated it and the readings were the same after calibration. Last time I had to start with base map again and manually change almost all the settings, copy and paste ign and ve maps to get back to normal again as reloading the actual saved map doesnt change anything. WEIRD ****!!

Matt Cramer

Could you also post a data log of the problem? This will give us more to go on.

ccsfd

Thanks for looking Matt, heres a couple logs taken 1 week ago and today.
Conditions are almost exactly identical but notice the difference in AFRs. The logs are a bit long so you can also look at some boost areas. but heres some telling points:
rough.msl @ 1241s date:May14 rich.msl @ start of log date:May 21
MAT: 18*C MAT:21*C
CLT: 96.8 CLT: 96.5
Idle RPM: 895 Idle RPM: 889
AFR: 14. AFR: 11.
IGT: 10.6 IGT:10.0

rich.msl

rough.msl

Matt Cramer

It looks like your AE is triggering too easily. Try increasing the threshold setting.

ccsfd

Il try that but that wouldnt affect idle afr with no throttle input would it? And it was running good even with that setting. When the idle afr changes it affects the whole map and i can feel it whn driving.
just wondering what might change it when it idles on the same VE spot with the same VE and ign settings and about the same engine conditions, no enrichments at all.The log doesnt show it but theres quite a difference in the driving feel-car feels slower. Is it possible theres bugs in the software, I dont know if thats possible i dont know much about computers/bugs.

Matt Cramer

Noise on the TPS can cause acceleration enrichment to false trigger everywhere.

ccsfd

Thanks Matt, did you notice that on the log? How can I tell noise on TPS?
when the car is idling with no throttle input the TPS gauge reads 0 and doesnt move at all. when you mentioned threshold is too low, does that create noise? really appreciate you trying to help.

Matt Cramer

The acceleration enrichment is triggering too easily and dumping a lot of extra fuel - even though the noise is often too short to actually show up on the TPS gauge.

Setting the TPSdot threshold too low doesn't create noise - it just causes the MS to respond to noise that is already present.

ccsfd

Thank you Matt, I'll have a try with the AE settings.