Well, after two tanks of fuel with 8 oz of Startron in each, the second tank topped off with about 6-8 oz of Startron Tank Cleaner at 1/2 level and 1/4 tank with about 10 oz of the Tank Cleaner my ENGINE RUNS SMOOTHER WITH NO PINGING!

I preemptively poo-pooed the Startron!

It works. It really, really works.

I will say that the tank cleaner smelled "soapier" than the regular maintenance stuff. The regular stuff has a much more volatile aroma.

I know that I had algae in my tank because of what I saw after I ran out of fuel.

The plastic primary filter screen was completely blocked up with what turned out to be very oily, slimy organic matter. One piece of the stuff was big enough to be stuck to the screen and the outer body of the filter.

And that is what made it past the tank screen...

I put a lot of miles on my car so if this were allowed to sit longer it might not take the same volume of fuel to accomplish what is has so far for me.

I couldn't believe it.

All day I had the same symptoms until I finished the last 120 mile leg of my work day and turned the engine off. I went inside, got my dogs, came back out and fired up the engine. I noticed immediately the engine ran as silently as it did when I bought it a month ago and the very scary pinging noises were either almost gone or barely audible at idle.

Before the treatment I had to give it almost half the pedal for the unusual (starved?) engine noises to go away. I also had to reach a certain RPM for before they would dissipate.

I stand corrected.

Startron works, especially the tank cleaner version. I hear, but haven't verified it myself, that it has twice the "enzymes" of the regular maintenance stuff.

Now I can move on to a timing chain and sprocket(s) change some time in the near future.

Thank you MercedesShop Forum posters.

This place is a gold mine of information.

__________________
1993 W124 300D
-297K on the clock as I type this.