Clogged exhaust like Benz

[vaman4215]

Well today my 84 300D started doing something that reminded me of olden days when my catalytic converter stopped up on my pickup truck...I line about 5 miles from my mother-in-laws house. Was going there for Christmas early supper tonight...Got about half way there, speed started dropping, no matter how far down I went on the pedal. I pulled over, got out checked under hood didn't see anything wrong...Got back in, went a little ways started doing same thing....Finally got to my in-laws doing 20 mph at best.....We ate supper, left got about halfway home again, same thing started happening....When I left in-laws car ran fine, had plenty of power, etc....No problems at all....I'm running a mix of dino diesel, kerosene and filtered wvo.....If my filter was getting clogged why would it be ok for a few miles after having the car cut shut off for a while???? Any ideas on what might cause this???? Never seen a diesel do this before.....