what do you have to loose by cleaning it? I looked at your pics and saw the light dust in there, that means it has got to the filter also, although your filter isn't caked with crud it still has picked up the fine dirt. I bought a extra foam element for mine, every 500/600 miles I just swap them out, clean the dirty one and place it in a zip'lock bag til the next time, i think its a good insurance policy IMO.