Question about 1999 Chevrolet Monte Carlo

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I have a 99 monte carlo with a 3.1, the check engine light came after I had changed the wires and plugs about a month ago, the code came back as p0401 egr insufficient air flow,I bought a new egr, gaskets, I had erased the code several times,only to have the light came back on after 40 miles, I just can't figure out what else could be wrong, The car has 150,000 miles on it. Thanks and have a great day Mark Z

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Remove the air tube to the throttle body. Open the throttle all the way and look inside with a flash light. You are looking for a lump of carbon at the egr port int the intake manifold.

Remove the egr valve, using a hanger or stiff wire, clean out the egr port removing the carbon from the intake manifold.

Posted on Sep 06, 2009

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