Seems like when I'm at freeway speeds most of the time, the needle just goes down past E and rests there. Sometimes it'll come back to life after I slow down to city driving again and sometimes it'll stay below E until I turn it off and start it up again. Anyone know whats going on here? Thanks.

Kind of sounds like the ground strap may have corroded and is losing contact or is intermittently getting you the signal... if not, it may be the sending unit itself...

-D.idiot