[Odrapnew]

EDIT: I'll leave original post below. I think part of the issue is pulse width. Under higher rpm, closed throttle, pulse width is about 0.7ms. Add the ~0.4ms battery offset and get a total of 1.1ms. I think this is just a bit too short for the injectors to open, so they don't flow any fuel.


I have Deka 60lb injectors, running GUFA (A9S) and have this issue where at rpms in the 2500+ range under closed throttle decel, AFR pegs lean. Most other driving conditions, AFR matches LAMBSE for the most part (closed loop).

For the most part, this isn't a problem, but I believe this is also causing my random closed throttle dying after longer decel before declutching because wideband shows pegged lean until it gets near idle and by that time the engine momentum isn't recoverable.

I disabled DFSO as I thought that was causing it, but no change.
I even went as far as commanding less than 10 AFR under very low loads in open loop closed throttle, no change.
So, commanding something like 9.8 AFR, my wideband pegs lean.
Under same maf voltage driving around, fueling seems fine.
I've gone through the engine multiple times checking for vacuum leaks and haven't found anything obvious.

I've tried changing low slope and breakpoint with no impact. Currently running 60lb high and low slopes.

I plan to datalog pulse width on my way home to see if I observe anything obvious there.

Any thoughts?