im new here and i am trying to see if any one can help me with my problem. i have a 1993 s10 blazer 4x4 it has the 4.3 vortec with 143k. when i got it you would have to hold the gas pedal to the floor befor it would start it would just crank and crank. after it would start and run rough till i reven it up a few times then it would run great. so i did a tune up (plugs,wires,cap,and rotor) still didnt fix it. so can someone help me out!!!

 

Test the fuel pressure, specifically key on, engine off and the leak down after the pump shuts off. I'm betting you have a fuel leak internal to the plenum. Very common on the CPI engines. Fuel pressure regulator on Blazer 4.3L CPI W engine <-- that should help shed some light on the subject.

 

I had that same issue on my 94 blazer, in my case it was the fuel pump that had gone bad, but the reason my fuel pump went bad is because my fuel pressure regulator had been on its way out for some time. I would start with the regulator as its farely easy to replace, just take the top half of the manifold off and its right there, just make sure you have torx bits because you need to take the plastic cover off the top of the engine as that hides a couple bolts, then you'll need torx bits and a swivel head to take the regulator out. Now the fuel pump, thats another story you need to drop the gas tank to get to it.

 

Hey thanks for all the input. But I have another queston now. I did something really stupit and now I can't get it right. I pulled the dist. Out with out marking where I took it out at and now I don't know where it goes back in it. I got it to run but it seems to have no power when I'm driving.can someone help me with it

 

You will have to set the timing, thats the only way you will get it to run right again.