Mercedes: 1991 190 E 2.6, jumper cable, ground cable


Question
Hi I Am Having Trouble With The Gas Gage And Oil Gage Thay Work Sometimes I Am Thinking It May Be A Ground Not Sure Where To Look The Fuse Is Good Hope To Here From You Thanks Brent!  

Answer
Have the charging system tested first.

Remove battery ground cable from body, clean cable/body contact points, reinstall, and test.

Before going further, connect a battery jumper cable to negative terminal, connect the other end to the engine, test the system, if your issues are gone = bad body/engine ground cable.

Replace all fuses with NEW, if they are over five years old.

Instrument cluster ground is a possible issue.