I have a 99 4x4 blazer. When i drive it normally and do not push it it drives and shifts fine. Whne i drive WOT from a dead stop it starts fine then bogs down hard at about 25-30mph still accelerates, but at a really slow pace and engine is still running at higher rpms but isn't puutin out much power as it used to. Also when driving on highway and trying to pass if I WOT it drops down in gear and bogs down if I let off throttle a little it has better gain in acceleration.

My blazer has 122,500 on it. I have a Transgo shift kit and a CAI. This has just recently been occuring that i Have noticed. It drove fine and had good shift points when I first got Shift Kit installed. What do I need to do to get her back?

 

When was the last time you performed a tune up (plugs, wires, cap, and rotor)?

Have you tried cleaning the MAF sensor? An aftermarket oiled air cleaner can coat the MAF sensor causing general driveability concerns.

 

I haven't done a tune-up yet. I am going to soon trying to figure out if it is something I shoud do myself, I am vairly confident that I can do it, except that difficult sparkplug. I was going to do a whole tune up with wires, plugs, rotor, cap. Anything else I should do while doing tune up. I a definetly going with ACDELCO parts from what I've read on here. Just have to find a place to buy everything.

Haven't thought about cleaning MAF I'll try that tonight when I get home.