|I installed Nismo 740cc injectors around September of last year. I've been storing the Z since December due to grad school and...these issues. I'm pretty sure this is a basic problem which either means rich/lean/air leak/fuel leak.
-If the car is cold and I step on the throttle the rpms will dip significantly before going where they should. Only happens in first and idling off the top of my head (been 5 months). Goes away when the car is warm (not 100% sure, but does lessen) - did not happen until new injectors were installed and tune was played with.
-When driving (doesn't matter if warm or cold, usually when downshifting) if I push the clutch in the car will occasionally stall. I have a feeling this has to do with the first issue. Never had stalling issues prior to 740s.
I only have one wideband o2 sensor and bung on driver side (strategic error) which makes diagnosis slightly more of a pita. Not providing afr's because the accuracy of my wideband has been called into question.
There is more to this, but these are the basic problems so I won't complicate things! Currently I have Nistune. Once I get things going smoothly I can finally justify SZ 3" (w/ two WB bungs!), Selin, and SZ/Harry/Ash tune.
Thanks for any input.