failed emisions twice after many repairs on 2000 Hyundai Sonata

had the egr cleaned, dpfe diferential feedback sensor replaced, replaced egr vaccuum, selenoid drive cycle performed twice, and the the car still failed emissions twice....and idea what is actually wrong? thanks

Asked by for the 2000 Hyundai Sonata
The EGR system is very complicated and suseptable to fouling due to the exhaust gases that flow through it. Without being able to look at the real time data from the computer, it would be impossible to pin down the source of the fault. EGR cleaning only works in a fraction of cases and often it is the tubes going to the valve that are what is restricted. It is going to take another round of diagnosis to find the solution. This may fall under the PA Emissions Waiver rules to get you through the inspection procedure - ask your shop. However it is always best to have the problem fixed properly to eliminate the pollution and potential harm to your motor. Thanks, Chuck-Baum Blvd Automotive