Ok, I'll push the gas to accelerate (normal-- gradual) and it will start going, but when it hits 1800-2000 RPM's it like gets stuck , itll drop down to 1500~ and go back up. Repeatedly until it breaks through that point (usually if I give it a little more gas). I have no idea what it could be. Sometimes it makes a backfiring noise around the engine. if I were to floor it, itll make a big backfiring noise under the engine. Ugh, i hate being dumb with cars. What does it sound like?