Hey guys, i bought my sandstorm buggies a month after Christmas of last year. Straight out of the box, my dads buggy ran smooth - break-in, everything normal, but my buggy did not. The problem i encountered (and still encountering) is that the engine will rev high with out me pressing the gas, it makes a sputtering sound, and if i give it gas to actually drive it - it keeps going even though I'm pressing the breaks. I've leaned in and out on both screws but nothing works and I'm wondering if this problem is fixable or should I just forget the engine and buy another.

Thanks in advance.