I have been having charging issues with my 87 240 and I have changed everything I can think of including re-routing the alt/oil light wires.After returning from a test ride I had the same results voltage was way down 12.11 volts at the batterie. had been 14.07 in the driveway idling. So I had an idea to see if the car would run on the alt by itself so I disconnected the ground cable on the batterie and it ran on the alt and I put my meter on the posivive post of the batterie(still connected)and the ground cable (disconnected) and my meter went up to 14.56 "hummm" so I then put my meter on the alt light connector on the rear of the alt and to ground ...14.56 volts there too. Could this be a bad groung cable going to the batterie? seeing that 14.56 volts coming from the alt with the ground disconnected was proving that it is working but something is holding it back. I am running out of ideas and really do not want to take it to the shop

getting desperate