Not sure which 2003 Chevy Trailblazer Performance Chips & Programmers are right for you? We have over 7429 customer reviews, with an average rating of 4.5, to help you find exactly what you're looking for. Here's what some of our customers have said:
"i installed the PCM on my 03 trailblazer 4.2L and i noticed better acceleration at about 3500rpm, but nothing really below that. there was also a distinct difference in the exhaust note throughout the entire rpm range. i have a 1" spacer kit, 265-75-16 nitto terra grappler tires, and a gibson exhaust. with all of this installed and the PCM, the acceleration feels like it did when it was stock without the spacer kit and bigger tires. i haven't noticed any real difference in MPG, but i have been driving a bit spirited recently." —Jesse G from Glenville, PA bought a Jet Performance Module for a 2003 Chevy Trailblazer, 4.2L 6-cyl..