Intermittent Oil Light 96 2.2L

My wifes car...she bought is new. Overall very good car. 196k miles. Have replace most of everything external once. Just got done with all 4 fuel injectors. From early on the car's oil light comes on....once during the day and then maybe not for two months again. Oil level good, changes every 3-5k miles.
So my question is...Has anyone had problems with the Oil Sending unit. And I am thinking of installing a mechanical gage with the light. Anyone done that ??
Thanks, HJ

Oh ya...I drive the car once a week..never done it for me. My wife is not a blonde !!!!ha ha