5.7L rebuilt idles rough

Very Recently had an ATK rebuilt 5.7L installed.Had a pretty good mechanic put it in, however idles rough at stops. Before i have to go back to him, I thought I would run thru a few options of what might be wrong.We replaced the (spider) fuel injection,fuel pump, fuel pump pressure, ignition module,rotor, plugs,plug wires,fuel filter,air filter.Might it be an EGR valve causing the problem? Also, he had installed a new cap from car quest and he developed a bad missing problem between #7,#2, so he replaced the new one with the old cap and it worked fine.However it didn't get rid of the idle problem.Where is the egr valve located at?What other things might it be considering before the old engine sucked coolant into the oil, it was running smooth.

What year truck are we talking about?

//2000CAYukon

1997 z71 extended cab

EGR can cause a rough idle. The EGR is located on the back of the manifold. If you look at the drivers side exhaust manifold you will see a pipe. If you follow that pipe you will find the EGR valve.

A worn bushing on the dist will also cause a rough idle.

Also check to make sure that there are no vacuum leaks.

//2000CAYukon

Thanks Yukon, will check those possibilities this weekend.