The 2005 Chevrolet TrailBlazer might possibly have a mass wind stream sensor; the 4.2L motor variation excluded it by and large. Assuming You have the 5.3L motor all things being equal,You'll find the sensor promptly beyond the air box on the flex hose. It ought to be generally easy to find,on the off chance that You understand what You're searching for. I suggest looking into a picture of the part so You have a respectable beginning stage. In the event that You're hoping to supplant,inhale a moan of help since it's a generally modest part. You'll find substitutions accessible through most major auto part stores for the $40 to $75 territory,contingent upon brand quality. Consolidate that with a basic trade work wise,and this makes for an ideal DIY project.