Cleaning of EGR Valve

My 95 3.8L has been throwing EGR valve codes ( P01406) for about 6 months...I remove it...clean it, replace the gasket and no problems for about a month.....then it comes back again. The last time is idled bad and hesiated worse than ever!

When I say clean it....I spray Carb cleaner on the valve, brush it.....spray cleaner down the ports.....

But is keep coming back....

Question: Should I be doing a "more" intense cleaning? If so...What should I do....