Im new on the forum but I have a good questio for you guys. I have a 02 xtreme with the 4.3 vortec and it feels like its either bogging out from getting to much air or its not shifting like the TPS is going out. I recently replaced my MAF and claned my air cleaner with a recharge kit(I have a cod air intake) with tempoarilyfixed my problems with high idle rpms and rough idlig. Now bth those problems have comebackwith friends. Now my truck likes to not shift with the throttle anywhere from alittle under halfway to fully engaged until about 45 or 55 out of first gear then all following shifts are very sparatic and iregular and just all around rough. Also sometimes it almost feels like I have a misfire in one of m cylinders or multiple cylinders. My blazer is at about 94800 mi I have no leaks or burning fluids. Oil gets changed every 3000 with castrol gtx high milage and fram tough guard high milage filter without fail sometimes a few miles early just because i have the money at the time. Ive had my radiator flushed professionally my gasket isnt busted(was told this is common in 4.3 vortec) and all this started today during a highway drive. I replaced the distrutor cap and rotor all plugs and wires fluids hecked and topped off new tensioner new motor and rear tranny mounts allithin the las four months. Im just lost and at my wits end. I love my truck but these repairs become costly(especially since i have a need to use OEM replacement parts and these seem to be more expensive) Any advice or tips or if you know what is wrong. Im listening becuz like I said Ive replaced many parts to preventproblems and its not helping