In late 2001 the model or last got its most significant host of upgrades, including minor revisions to the interior, new optional equipment, larger brakes, a re-tuned suspension system, and standard stability control. The car was renamed I35 to reflect an engine-displacement increase from 3.0 to 3.5 L. Nissan's VQ35DE V6 produced 255 hp (190 kW). Styling was also updated.

Infiniti wanted to convince buyers that the new suspension tuning, enlarged brakes, stability control and 255 horsepower engine had transformed the I into more of a sports sedan and less of sedate entry-level model, but was largely unsuccessful. The model was only available with a 4-speed automatic transmission and front wheel drive, meaning that the ES300 and Acura's pre-existing second generation 3.2TL remained its closest competitors, with models like the BMW 5-Series remaining out of its league.