My 87 300E has 316K miles. The gas guage occ will change from a correct reading to zero to 1/4 back to normal. Sometimes the jumping is almost continuous and other times not.
Is this most likely a sender problem or dash problem? If a sender problem is it usually a contact cleaning or replacement of sender?
If a dash problem is there a contact to clean? I may pull the dash anyway to get my trip odometer fixed(nobody local-plan to send to Hollywood if no other suggestions.)
Thanks

Likely a sending unit full of gunk. I recall seeing a web site by where someone to the unit out, cleaned it and re-installed.

Could also be a poor gound, either the sending unit end or the guage.

Let us know what you find.

__________________
Greg
'73 416 UNIMOG DoKa
'85 300GD G Wagen

Previous thread on how to clean a sending unit on a diesel.

http://www.peachparts.com/shopforum/showthread.php?threadid=38776

Check the ground to the instrument cluster, maybe loose.