What can cause to car to buck

I could be a few things but here is a couple of things you can try. Check air filter clean throttle body with throttle body cleaner spray and replace fuel filter if have not done so in a while. Add fuel injector cleaner to gas tank.

My car was bucking because transmission fluid was no good and filter was clogged after replacing fluid and filter the car stopped bucking, it could be the same problem, but there is six other things that can make car buck fluid, filter, transmission speed sensor, input sensor, output sensor, leak in transmission line, or transmission is going.