(Volvo 744 gle) Hello im new to fixing cars and i was trying to get a kinda external fuel guage and i took the wires to it and clipped them and the rpm meter stopped working🤔 even though the wires are not for the rpm meter when i was trying to get the guage house back in place something held it back and i took it out snd in again, can i have broken a piece of something important?? Kinda need to get this working👍

 

Check out volvotips.com - you should find a wiring diagram there. Look for common wires between the fuel gauge and the tachometer - my bet is you disconnected a common ground point.