Two months ago I accidentally plugged my Breather Hose on my prize 1985 300D and ran my Oil down to a quart or less
;honest ,the oil pressure was down to 0 Bars.
The car was already having performance issues which was why I was working on it and accidentally plugged the breather hose by crimping it.
After that the Car was Dead, I mean really gone. It Smoked like a Demon. It had no power and it lost almost a quart and a half of oil every day--for a while almost two quarts a day. At idle, it sounded as if the engine would jump out of the engine compartment any minute..it scared my carpool mate.
I figured I would keep the car anyway because I had rebuilt the Air Conditioning and it was Ice Cold, like that of a new car and in case I found an engine.
I went out and bought a 1987 300D.
One week later the injectors I bought on EBAY for 75$ came in the mail. I figured I would plug them in anyway...I also gave the car a couple of Poor Man's tune ups, running it down the highway at 90 mph like one Post advised and I took it on grueling stop and go trip to NY City because I figured it might get hit in that traffic and I didnt want to take my new 300D 1987.
A couple of weeks I used it a couple of times in the heat because it had AC. It had stopped Smoking! Its doesnt use oil anymore! A couple of tweaks, like a solved vacuum leak, and the Car runs great now.
What this tells me is that Diesels defy analysis and there is a little Black magic involved in troubleshooting and using them. I still cant believe my luck. I bought the 87 300D for $2K, a really nice car, but I love my W123 and I havent driven the 87 for two weeks now, I just love the W123 more--it feels like a comfortable pair of shoes or jeans--I havent fixed the 87 300D's AC--and am considering selling it..