I've got a rack-damper bolt question that I couldn't turn up an answer to in the search. A little background to the issue might help...sorry for the novel.

My buddy gifted me a 1983 300TD Turbo with 330,000 miles in pretty tired condition as a beater/project car. It runs pretty strong and starts really easily, but soon after I got it, it very suddenly developed a real bad shake at warm idle. Sometimes it's worse than others, but the shake almost never starts before the car is at running temp. It feels a lot like a misfire but goes away the second you get on the gas even a little.

I did some research and tried a diesel purge, changed all the filters and the fuel lines as well as fresh diesel. While this freed up some mid to high range power, it did nothing for the shake. Next I changed the motor and tranny mounts as they were collapsed. I had to skip the engine shocks as I couldn't afford the ridiculously priced bushings, so for now, the car only has one working engine shock. Still, the new mounts didn't help the shake much once it started. I don't think the absence of one shock is the cause of this as it's probably been a decade since this car had them functioning.

Next I decided it would be good to "force" a misfire. So at idle, I cracked each injector line bolt and each cylinder reacted noticeably to the forced-miss. While the shake my car gets does feel like a misfire, it's not as sluggish as a forced-misfire, it feels almost more "productive" if that makes any sense.

I've essentially come to the conclusion this is at worst a bum cylinder and at best a valve job/injector rebuild. Neither of which I have the money to buy the parts/tools to do currently. So in lieu, I decided to mess with the ALDA which someone had clearly bypassed and taken the fuel enrichment nut cap off of. I richened up the fuel and it seems to have helped a bit with the shake as well as freed up low end power. The car hauls ass now!

Lastly, I adjusted the rack damper bolt. First I adjusted it out, and noticed the idle shake got awful quick, so I started to screw it back in. As I screwed it in, I very quickly realized that it had been set all the way in originally! From my understanding, the bolt should not need to be all the way in. I'm curious if this is a sign of a dead rack damper bolt? I've included a picture. I still think this is probably a compression or injector issue but I really noticed the engine smooth out as the bolt went in. I'm driving it now with the bolt all the way in and it drives great and starts very easily. Still, while the shake seems to not come as hard, often or frequently, it hasn't fixed the issue. I've included a pic below.

Also, on another note, a lot of black engine oil came out with the rack damper bolt, is it normal to have engine oil in that part of the IP?

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