Revealing mistake: Season 5 Episode 4X4. When Warrick and the young coroner are examining the dead woman in the RV, look closely as you can see her blink.
Continuity mistake: The Pontiac Fiero that is seen underneath the Hummer is a different (but newer) model than the one that was briefly seen driving away from the taco stand.
Answer: The episode on CSI:NY was called "Love Runs Cold" and first aired on October 4, 2006 (Season 3, Episode 3) and involves the investigation of a model found stabbed to death by an ice dagger.
OneHappyHusky