Chevrolet: engine runing rough, camaro z28, egr valve

Question
well when you start the car its a six speed and its missing,and when your driving or takeing off in first gear it jerks at low rpms and also when your at 6 gear and give it some gas it also jerks the plugs were changed around 5 months ago,and wires put the same plugs in that the books recomded,also the wires were not the best wires ,to buy but they did recomded those types of wires what are the chances of being the fuel pump ,,,, thanks tony   
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Followup To

Question -
i have a 1994 camaro Z28 350 5.7 Lt1 motor so far i have replaced plugs wires,distruberto cap and rotor kit and coil pack,it was runinig great till it started missing ,,even replaced the calatic converter,and still runing rough,what can i do next like i said it was runing great,and then it started mising ,,dont know what else to do can you give me some kind of advice,,,  thanks tony

Answer -
When you say it runs rough, what exactly do you mean?

Does it do this right from when you start the car or only after it heats up? Any particular rpm?

When was the last time you changed the plugs and wires?

Answer
Ok it sounds like an EGR or fuel issue. My guess would be the EGR.

Are you able to hook up a fuel pressure guage to see what the psi is at idle?

When you turn the key half way, does the fuel pump sound unusually loud?

When was the last time you changed the fuel filter?

If it is the EGR, the air pump could have gone bad, or the EGR valve in the back of the intake manifold.

Check the fuel psi and change the fuel filter first and get back to me and then we'll test the EGR.