[schatzidog]

headlesshorseman - This is an absolutely great article. After getting P00401 and P00403 codes on my Washington state emissions test for a 97 Dodge Grand Caravan, I took my car into the local Shell station and was told that it would be $150 for a new EGR valve, $180 for labor, $45 for new vacuum tubes, for a grand total of $375. After reading your great how-to, I built the courage to try it myself. For $75, I was able to replace the old EGR assembly with a new one, in about an hour. Everything worked as advertised. Thanks!
One interesting note, I immedately took the van back to the emissions testing center, and was told that the diagnostic system will actually show as "not ready" until the car is stopped and started several times. They recommended I come back in a couple days, which I did, and had no problems.