Hi, I need some help. My 82 300SD with 255000 miles has NO acceleration/power off the line. It has been noticeable for about 6 months but has really gotten worse the last month or so. The valves are adjusted properly, air filter clean, fuel and oil filters are 3 months old and changed often. There is no fuel dripping out of the system. Only occasional light moisture, not enough to drip, at the #3 fuel line on the pump. I have light black smoke at startup and at cruise speed. It smokes real good when the rpm's go above ~4500 when shifting. It runs ok at cruise speed anything above ~2300 rpm, turbo kick-in speed. I have also been having a harder time starting in cold weather. The glow system works. Starts ok in warm weather. The acceleration problem only gets a little better after the engine warm-up. I checked the vacuum lines they look intact and all of the throttle linkages look good. The timing chain is original but appears in good condition. I have never messed with the pump timing. The factory or a dealer put an alignment mark on it and it stills linesup. The problem is accelerating from a stop. Full throttle, AC off and shift into low you would swear you could push the car faster the first two car lengths. Once it finally gets rolling it accelerates ok and even has the nerve to occasionally chirp the new tires as it shift into second gear. I hope I gave you enough info to help make a diagnosis that will graduate me out of the turtle drag racing category.

Any help greatly appreciated.

Thanks

Ulf