OK, so I still haven't changed my injectors or my oil. I entered a car show the weekend after this one and I want to work on detailing now, so I will change out the injectors later this month.

Looks like the consensus is that 15w-40 conventional oil would be the proper oil for my engine. Problem is, I have an unopened 5 quart bottle of expensive Mobil-1 5w-40 Turbo Diesel truck synthetic that's been sitting in my garage for half a year now. Anyone want to buy it?

Otherwise, I was thinking of using that up first, since I already have it....

In the meantime, I treated my tank with Star-Tron (fuel prefilter was black again), did a diesel purge (had two cans of that around, so why not), changed fuel filter, and haven't had any more random nailing under light acceleration. However, all is not well...there is a rhythmic, metallic "tapping" at hot idle after heavy acceleration. It goes away after about 5 seconds, so I can't locate its source. I hope it's just the bad injector and not something more ominous.

I replaced the injector return lines because 3 were leaking. I hope I can reuse them when I change the injectors. I changed coolant & brake fluid today also.

Valves were ALL tight. A new valve cover gasket fixed one oil leak. I hadn't gone 15,000 miles since the last valve adjustment, but I have read that sometimes if the valves hadn't been adjusted for a long time (like with the previous owner), they will go tight again in a short while after adjustment.

Now that valves are to spec, I'm wondering if the missing after a cold start will be gone now. I'll find out tomorrow, but I'm not holding my breath.

__________________
1976 240D "Katja"