I recently did a injection pump delivery valve o-ring job on my 93 300D and it seems to have a slight miss or studder at idle. You can feel it studder at idle in the car. Now I havent really drove the car that far yet, approx 15 miles. Will this go away or should I take it apart again?

It will go away. It's air in the lines. It will take a while to purge out. Maybe a couple hundred miles.

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92 300D 2.5L OM602 OBK #59

Agreed. Could be air that needs to be purged. I did my delivery valve o-rings recently - although, I also replaced all my plastic fuel lines and braided returned lines, and rebuilt the fuel pump. Point being, I got a lot of air in the system. Aside from being a real PITA to get started after that job, it knocked real hard for a bit - enough to make me think I really screwed something up. It eventually smoothed out and got back to normal. Give it a little time and see if it improves. Check out your fuel lines to see if there are any bubbles present. Watch for leaks. I let it run for awhile and then shut it down and let it sit for a bit. Once I started it back up the knock was gone.

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'95 E300D ("Tank") - 231,000 miles
'79 240D ("Biscuit") - 197,250 miles (Sold)
'83 240D ("Ding-Ding") - 217,000 miles (Death by deer)
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