Faulty Fuel Gauge?? 1998 E300DT
 

Hello,

I noticed that when I fill up my fuel tank (with diesel), the fuel gauge doesn't go all the way up. In fact, it is almost 1/8 down from the top mark, after filling it up.

When filling, I make sure to put as much fuel as possible.

Can anyone suggest where the problem might be? I hope it can be easily
fixed??

Thank you.

Lagging fuel guage
 

cayman 73,

Most likely the guage problem is caused by an accumulation of diesel fuel residue on the sender slider. The sender is a long tube that is affixed vertically in the tank and the slider moves up and down with the fuel level. The tube can be taken apart and the crud cleaned off. I think there is a DIY thread on the subject. And after all the empty end of the guage is the most important. When you have filled the tank you know it's full.

Can you get B99 or B100 biodiesel where you are? A tank or two of that would help take care of any sludge or grime building up on the fuel level sender. Just make sure you also have a spare fuel filter in the trunk, as that gunk is likely to wash upstream and clog up a filter. If that is in fact the issue, I bet some bio would take quick care of it.

Cheers, John