2ZR Turbo Yaris

[06YarisRS]

Stuttering/ bucking at low boost

I've been doing some research on my bucking issue at moderate throttle between 1 and 3 psi. I compared the tuner's map and the basemap for TK. The fuel cell values in that area of the maps are identical, so not sure what's causing that since it started doing it after my tune. The tuner recommends adding some fuel in those cells. I"ll test drive, replicating the stuttering and monitor my AFRs. If lean, I'll add some fuel. The research I did suggests a couple possibilities. 1) radical changes in adjacent cells can cause bucking at certain loads, or 2) I need to wire in parallel a 2.2K ohm resistor between the crank mag wires. Apparently several turboed Scion cars have this issue. Boomslang started adding these resistors to there PnP harnesses around 2007. I have a 2008 Scion ECU.