I spotted it in the first image in it's originally state. (It's just more blatant in your enlarged shot)It may just be becouse the image is zoomed and artifacts apear such as the blocky "aura" around lights. But it may also be a heat-haze effect (the relief effect may have changed the lines to be "croky"). The 2 first image parts have no relief.
To me, it's as plain as the nose on my face that both versions have heat haze and the only problem might be the way the devs have decided to stop the effect when the boosters are no longer active. I have seen it in games before when you stop accelerating or whatever, the heat haze stops as well despite the fact in the real world it wouldn't.
It's definitely heat haze in my opinion.