I just took the filter off to clean it, looked inside the intake tube and it looked like there was dust in the tube. I rubbed my finger against the walls of the tube, and sure enough my finger had dust on it. I thought this filter filtered good? It was a new filter, this is the first time cleaning it, around 8,000 miles on it. I checked all the connections, everything is sealed no ripped boots or anything. Why the heck is there dust in the intake tube?