Pesky P0404 code 99 Silverado

Pesky P0404 code 99 Silverado code p0404 P0404 means that one of the EGR valves is not working at all but if correct, this could be the end of my 'searching' to establish the cause of my P0404 RP code 369 club The P0404 code error comes when the EGR doesn't behave as it should Most of the time, it's because the valve doesn't open Besides the valve

code 369 club P0404 is a EGR circuit code You most likely have an exhaust or intake leak which is why it's running rich Check the engine bay for soot or oil

code p404 Some vehicles may store EGR control performance code P0404 This occurs when the difference between commanded and actual EGR valve position is more than 10% This code points to either carbon buildup or a bad EGR valve However that doesn't rule out the following: