Ok this is what I have done, lower cylinder does not run uless rpm is at 2000 or better ,did a compression test,both cylinders at 100 psi when warm. ,changed pgm and coil , plugs,started to think carb but squirted some fuel in carb while running did not fire off cylinder,i'll take any suggestions for help could it be throttle position sencer or could it sill be carb,i dropped the needle thinking it was to rich because it was smoking way to much, if its electricle were else should i look ?