As noted in this answer, Barry can run through time when he hits mach 2. Until recently, this was considered his top speed.
In the episode Trajectory (S02E16), Barry is told that he needs to run mach 3.3 to be able to run through the air.
Barry, to make that jump, you'll need to go Mach 3.3, but only for a second.
Barry successfully makes the jump, and does not travel through time.
Using standard, non common-core math, 3.3 > 2.0.
Given that Barry now has a new top speed, which he will undoubtedly have to use to fight villains and save people, how does he run faster than mach 2, and keep from running through time when he doesn't want to, or looking at it another way, what else besides speed is required to travel through time?
Of note, Trajectory was able to run faster than Barry, and Zoom is able to supposedly run 10 times Barry's speed previous to this episode, and also does not appear to accidentally run through time.
(I prefer an answer from the Arrowverse, but I'll accept an answer from the comics if this is sufficiently explained there.)