2000 monte carlo has no accleration ,threw a egr code replace . Still does the same no power.
I'm thinking O2 sensors.
Catalytic converter may have melted down.. Too much back pressure will reduce power and throw emission codes as well.
Try this, unplug the EGR valve then clear the computer using a scan tool. Turn off the ignition and plug the EGR valve back in. This will allow the computer to "learn" the closed position of the new EGR valve. If your Monte Carlo has the 3.8 have the upper and lower intake manifold gaskets been done yet? Could be time. They're notorious for failure. HTH. -Jim
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