My 2000 zr2 blazer has 130,000 on it and I can't figure out for the life of me what's wrong with it. It idles fine, but when I take it up between 1500 and 2000rpm it hesitates and chuggs. I also notice going down the highway it will run fine till I ease off the petal and it does the same. I have replaced cap, rotor, plugs and wires, cleaned the egr valve and even whent as fas as cleaning the cat converter out thinking it was plugged and still the problem continues. Anyone have any ideas before I go spending a fortune, or have had the same problems please reply!?

Sincerely,
goin f@$kin crazy!

 

hello have you changed the fuel filter lately it may be a cheep fix
thanks

 

MAF sensor

 

You could try cleaning your MAF sensor (procedure is in the Tech Article section). You could also test the TPS sensor. It could have a dead spot that leaves the computer wondering what to do..

 

Thanks for the help guys, I have replaced the fuel filter not too long ago but I'll try the other suggestions and let ya know.