From Longman Dictionary of Contemporary Englishstep on itstep on it (also step on the gas American English) spokenFAST/QUICK to drive faster → step
Examples from the Corpus
step on it• Fader - Looks like a normal block, but crumbles away when you step on it!• He was bold to ask that angels be sent, and step on it.• The third step creaked as he stepped on it.• The Corporal and I shouted at the Sergeant to step on it, as the explosions were getting closer.• You'll have to step on it if you're going to be there by eleven thirty.• Step on it. We have a plane to catch.• If you don't step on it we'll miss the plane. 