Issues with acceleration

[LiquidOC]

So I was a bad boy and overheated the engine and blew a coolant hose that made the head need redecked. Shop put it back together and now it won't always go when you hit the gas pedal, and sometimes surges while the gas pedal isn't getting it's position changed while going highway speeds. I'm wondering if maybe it's related to the gas pedal or throttle position sensor? Anyone know any ways of testing these? I have no CEL or anything else.

 

[LiquidOC]

I have some more symptoms.

It is very intermittent.

It appears through my OBD-II and the torque app that the car is going into negative timing while this happens, and I can hear a clicking happening from the engine bay while this issue is present, and the clicking/tapping goes away when this issue is not present.

Sometimes it's during slow speed, my gas pedal feels like I'm just pushing it randomly, even though it's held steady.

Still no CEL's, or any other symptoms. Gas mileage is still good. I pulled my spark plugs and they're all gapped around .26 (I don't have a re-gapper, but I do have a gauge.) But they do smell "rich", if that makes sense. Like not fully burnt fuel.

Please help, I'm at a loss.