Engine builder/tuner is having an issue and I?m trying to do some research in the back ground. 2015 SRT grand Cherokee. 2.9 whipple custom tune. Had 850cc FIC?s. Just had the motor fully built, pistons (10.1:1), rods, bearings, stage 2 PD cam kit from HHP, 1000cc FIC?s. Tuner said immediately after cold start injector pulse width on cyl #1 drops to zero. He can?t figure it out. Verified all plugs are connected, traced wiring, etc. Any help?