No additive or magic cure in a bottle will fix this issue, you will need to remove the sender from the tank and clean it plus fix any broken wires.

This tells you were it is located

PeachPartsWiki: Fuel Level Sending Unit replacement

And this thread will fill you in on whats inside it.

Fuel Sender 85 300D- Cleaned (Pics)

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the work around for this is to fill it up and reset the trip OD, I'm guessing you have a 17 gallon tank and to be safe figure 25 miles to the gallon. refill when the trip od hits 350 miles. You can start running Bio Diesel it may fix itself

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1993 MB 300D 245K died.

There is a Startron version for diesel engines. In the past, someone claimed that he had talked to the manufacturer and was told that the gasoline and diesel products were the same except that the diesel version was more concentrated.

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When cryptography is outlawed, bayl bhgynjf jvyy unir cevinpl.

L.J.,

If you can't find the Diesel Version it's O.K. to use the "Gas" Startron. It's simply a less concentrated solution of Startron.

Bio-Diesel IS a Great Solvent!

BUT, If your Diesel Fuel system ALREADY has an Infestation; ADDING Bio-Diesel
will ONLY exacerbate the Problem!!!

Comparatively,Adding Bio-Diesel to an already infected system is just like adding
Pure Oxygen to an already Raging Fire!!!

Whatever your problems are,adding Bio-Diesel to them only makes them WORSE.

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'84 300SD sold
124.128

The U.S. D.O.D. (Can y'all say "Anchors Away" and/or F35) will successfully
complete it's "Self Supply" Bio-Diesel programs before 2025.
NO MORE FOREIGN fuel supply dependence.


BUT! Unless you're a Chemist and/or willing to devote Lotsa Personal free time;
Going over to the "Dark Side" of Compression Ignition Fuels for Personal Automotive use,
just adds further complications to Modern Motoring.

[Doan Needs NO Flame Suit,Cranium already Invaded by Cellular Microwaves!]

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'84 300SD sold
124.128

Ity , Bump

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'84 300SD sold
124.128

Thanks makes sense

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1993 MB 300D 245K died.