My 1982 300D leaves a cloud of smoke when I really step on the pedal. The smoke is not really thick, you can see through it, not heavy black like some trucks I have seen. It is very visible in late afternoon when the sun is lower in in the sky. Yesterday I left a large cloud of smoke when I jetted (if you can call it Jetting in a 300D) across the road. It was still hanging in the air after I turned and looked back. I changed the air filter and that did not make any difference. I am thinking maybe the EGR valve or timing? Thanks for any help.