still sssmoking

[zbys]

Hello everyone
I developed a sssmoking problem on a 81 300D.The problem occurred suddenly. Checked the injectors, they look pretty good for 160K.Changed fuel filters. Car In the beginning idles very rough, eventually even out, but is not as strong, when I put it in drive holding the brake the engine is as if pulling a heavy load. When changing fuel filter #2, the one with the bolt. I noticed that there is a rubber washer located around the bolt that was disintegrated; pieces of it were located in the opening at the top of the bolt. My question is can it be possible that some particles got into the fuel pump, and clogged something up? If yes how do I approach this problem? Any suggestions are appreciated.