hi everyone great site I have a 94 s10 blazer cpi which I am having a heck of a time with lately when I start it up itruns and starts fine at idlebut when I hit the gas at about 2900rpm it starts to run horrible it wont exceed 3300rpm the fuel pressure at idle is 55psi on the throttle its 60-62psi I have new plugs,cap,rotor,coil,fuel filter,plenum gasket,and c.p.i.unit installed already when it starts missing (badly) the fuel psi is still good about 60psi it just dies off like theres a rev limiter on it or something I have checked and done everything imagineable any suggestions would be greatly appreciated I dont want to have to retire my blazer with only 60,000 on the new motor 225,000 on the truckI've had it for to long and love it please someone help

 

Classic symptoms of a failed catalytic converter.

 

I think there isa good chance your right. I got under the truck after I started it and could here the catalytic converterrattling. I grabbed all the shrouds and held them tight to make sure it was the cat. It is coming from inside the cat. I will let you know how it turns out thanks a buch.

 

try pulling the O2 sensor out and see if it runs smoother. If it does then you are probably looking at the Cat.

 

After 1 year of troubleshooting it runs like a top again thanks a lot. Perfect diagnosis