large pulse width but lean afr
 

So I recently have got my vvt swapped miata broken in(on stock ecu) and have now installed my MS3 basic.

All has been going well but I started to see this odd issue in my regular cruise condition. between 2200-2800rpm at low load it begins to run lean(afrs from 16-17) and it surges/kicks/bucks. No matter how much fuel I have added it stays the same and so I pulled a data log and my PW signal matches my VE map but AFR almost seems to have an inverted correlation in this one area. My only idea at this point is to check for vacuum leaks but I have not found anyone who has had this issue but I do struggle sometimes finding specific issues being discussed.

https://cimg4.ibsrv.net/gimg/www.mia...9a518cdf83.jpg


msq and data log also attached

Is it possible that I'm getting a misfire(probably from so much fuel being injected) so unburned air is giving a lean reading? I think that I will try going back to the base map I started with in that area and see if that is the issue. Although I wont be able to make any changes until next week due to going out of town for the weekend, just wanted to see if I am on the right train of thought on this issue.

Also I will be checking for any vacuum leaks but last time i checked it all looked good.

either leak/misfire, or possibly bad connection to 1 of the injectors causing it to stop working intermittently.

unlock your spark advance. retune. enjoy HP.

Are you using a CAS on the exhaust cam?

Connections should be good( I just replaced all the old original cracked ones with brand new ones from Japan lol), but yea, I'll definitely check for leaks.

Whoops, I'm still new if you cant tell haha forgot to unlock it after setting timing months ago as I have been working on this here in there.

Yes, I am running the 1.6 CAS on the EX cam for now and am currently finishing up building a harness for the NB sensors and VVT. Ive already done TPS and idle control, just trying to do one thing at a time so i dont get lost on what causes the issues I see.

Thanks guys