I really love this piece. Repetition is a hard card to play, but you used it in just the right way for the best possible impact. The change in style and format as the piece transitions is a great way to force the reader to change gears - all in all, just a great piece. I've got some nitpicks, but they're easy fixes or personal calls.
"it’s rays lash my corneas like whips." - its. If you wouldn't say "it is", it's not it's.
"At every intersection I wait behind thrumming exhausts and red brake-lights." - May want a comma after 'intersection'. Not strictly required, but your pace comes from a lot of short sentences so far. Why break it?
"The kids are thirsty, the baby’s crying." - the comma here feels awkward. Maybe best to make them two short sentences.
"My god we’re like sailors lost at urban sea." - might want a comma after 'my god'.
" I sit in the car and lean against window" - lean against 'the' window?
"I’m at a light. the engine drones." - Is the lack of capitalization intentional? If so, 'I look down at my lap' throws off that concept.
Thanks for putting this up - I had a lot of fun with it. Write on!