im new here just got a 91 blazer 4.3 tbi did fuel filter plugs wires cap/rotor still falls face down wen i give it more gas plz i need help its gettin cold im MN THX GUYS

 

Fuel filter? Air filter? All vacuum lines correct and not leaking? Please provide some additional information on how it acts.

 

yes i have checked all that stuff and replaced the easy stuff....Well i start it and it runs fine smooth i goto put it in gear and it will only rev so high and it boggs down.In park idles great im just stumped not sure any thing will help me lol thx...

 

Sounds like your catalytic converter may be plugged.