So ive been working on my 2000 chevy astro for 4 months now. Ive replaced alot of stuff. Ive replaced the cap and rotor,the ignition module, cam shaft sensor,crank shaft positiin sensor,ignition coil, fuel filter, thermostat, mass air flow sensor. My astro starts it runs for 15 20 minutes drives great but then it hits it starts studdering will not pick up speed and dies out. It will start and run everytime but always die. Any advice would be greatfull to have. I believe that ots probably the catalac converter or the muffler theres i ton of stuff in the muffler of i hit it. It also back fires if i keep teying to give gas before it dies out?

 

I would try monitoring the fuel pressure

 

I monitored the fuel when it first started and replaced the fuel filter because it wasnt cranking up at all and after i did that it now starts and runs and what i wrote in this post is whats going on. I really am at a lose?

 

what was the fuel pressure?

Did you check the plugs?