I think it's tune related. My current tune is super rich, high 9's low 10's, and until I get the tune ironed out on gasoline I'm wasting my time playing with the injection system. Having said that, it doesn't "surge" when the injection system is off. When it happens it feels like the motor quits and then starts at wot. It only jolts hard once but it's a hard jolt or surge. The shop used the 5 gph nozzle but it's set to reach full pressure at 25 psi which it never reaches. On these tunes the throttle body opens and closes at an accelerated rate and perhaps the speed it's closing is contributing. IDK. The shop told me a car would drown out the spark at an AFR of around 9.4 which is the reason I mentioned it as a possibility. We shall see when all the apples fall off the tree.

Les