I put ID850 injectors in my 2008 STi.
Before this, my trims were all zero, and under boost the target fueling was dead on with a wideband. So I'm pretty sure my MAF tuning is good.
Now with the ID850's, I can't get both the trims and the open loop to line up.
ID publishes the latentices for the injectors. If I put these in, I need a flow scaling of ~800cc/min to get nice even 0% trims. However, then under boost it runs about 10% rich. I'm only boosting the wastegate pressure of 13PSI for my turbo right now.
If I put in 885cc/min, which is what the injectors are rated at, I get perfect AFR's under boost, but my cruise trims are off up to 10% (the ECU is adding fuel under cruise).
The weird thing is that the trims add more fuel as my MAP goes to less vacuum, so I'd think a vacuum leak would need more fuel added at idle, not at near 0 vacuum. This could just be the latentcy being of a touch though.
I've checked for a vacuum leak, but I can check again..
Is there anything but a leak that could cause this issue? Am I missing anything but injector scaling and latentcies?