Toyota GR86, 86, FR-S and Subaru BRZ Forum & Owners Community - FT86CLUB - View Single Post - Feels like DI isn't kicking in but no CEL

4n0m41y · 07-24-2021, 02:11 PM

@steve99

Reseated the DI computer bolts, checked all plugs, cleaned maf sensor, reset ecu (by pulling negative from battery). Took it out for a spin and these are the results (got two really good third gear pulls on this log): https://datazap.me/u/ziltoid/004-res...f?log=0&data=1

Driving down low feels solid, mid range from like 4500-5500 seems kinda soggy, and then after 5500ish seems to pick back up a bit. You had mentioned that commanded afr and reported afr should generally be within 4% of each other, so I wrote a script to calculate out that percentage for the log (just to give me some value to look at to be like, yeah that's lean or yeah that looks good) and low and behold from about 4500-5500 she still appears to be running on the lean side.

You think being lean in this range could simply be from needing some adjustments to the default stage 1 oft tune? I had mentioned (I believe) before that my intake was stock...that's basically true, but it might be worth mentioning that I have a perrin intake tube running from the factory air box to the tb, and a k&n filter. Maf is still in factory location and everything. Think that could have something to do with it?

07-24-2021, 02:11 PM	#32
4n0m41y Member Join Date: Oct 2013 Drives: 2013 Scion FR-S Location: Missouri Posts: 22 Thanks: 6 Thanked 4 Times in 3 Posts Mentioned: 0 Post(s) Tagged: 0 Thread(s)	@steve99 Reseated the DI computer bolts, checked all plugs, cleaned maf sensor, reset ecu (by pulling negative from battery). Took it out for a spin and these are the results (got two really good third gear pulls on this log): https://datazap.me/u/ziltoid/004-res...f?log=0&data=1 Driving down low feels solid, mid range from like 4500-5500 seems kinda soggy, and then after 5500ish seems to pick back up a bit. You had mentioned that commanded afr and reported afr should generally be within 4% of each other, so I wrote a script to calculate out that percentage for the log (just to give me some value to look at to be like, yeah that's lean or yeah that looks good) and low and behold from about 4500-5500 she still appears to be running on the lean side. You think being lean in this range could simply be from needing some adjustments to the default stage 1 oft tune? I had mentioned (I believe) before that my intake was stock...that's basically true, but it might be worth mentioning that I have a perrin intake tube running from the factory air box to the tb, and a k&n filter. Maf is still in factory location and everything. Think that could have something to do with it? Attached Images