oil pressure light comes on

[kevinw]

question. I have a 69 Malibu. just got the dash lites working, and oil pressure lite comes on when I turn on dash lites. checked bulbs and made sure ground is ok. now, I noticed even without dash lites on, the pressure lite comes on. (I know its not a oil issue). anyway, I fiddle with the light switch on dash and turn it where dome lite comes on and off, and sometimes oil pressure lite will then go off.
is this a problem with lite switch you think, or maybe a bad sending unit?
thanks