had a similiar issue with my sr. If I full throttled the car would break up like a boost leak. Did a boost leak test an it was all good. Checked voltage to cas, tps, an maf all good there. Changed fuel filter an plugs made a lil difference but still was breaking up on full throttle. I pulled the harness and part of the harness going to the coil pack harness was fried up, replaced the section an haven't had any issues yet, gl