Hi guys I'm new here and having a very hard time tracking down a coupld of problems. I have a 90 f250 4x4 with a 5.0, 5 speed manuel. the problems I am having is starting with the first one, a short I can't find. When I drive the amp meter drops down to about nothing, the oil pressure and temp guage goes way up and the lights dim. It also has a miss. I bought this truck aobut 9 months ago and went thru and did all the regular things like tune up and the like when you buy something from a private party. the short began to get worse about 2 months later. and has steady gotten worse. Worse in that it was an every now and then thing to all the time now.
the second problem is a fuel problem. I was told that is not getting enough pressure to the rail. the regulator checked fine, I put on a new filter. I have duel tanks and was told that it was the fuel pumps. What doesn't make sense if both pumps (in tank) are going bad how do they go bad at exactly the same time and same rate. I could see that maybe going bad at the same time but when you change tanks the engine runs just the same with no difference in at all.
Please any help ideas or thoughts.

 

Last nightI was looking for the fuel tank selector valve and now the amp meter is bouncing between ok and down. Not sure if I mentioned that the lights dim way down at the same time.