How do you know if it's a bad pump or sending unit?

[scrisp2]

Recently, my 04 Cruiser (n/a version) has had the oil pressure light coming on. It doesn't do it all the time and doesn't do it while driving, only when it first starts up.

If it comes on, I can turn the motor off and restart it and it goes off after a second or two.

Could this be an oil pump going bad or a sending unit? How would you be able to tell the difference?

It's got 76,000 miles and is about 1000 miles past the oil change time (it's at around 4000 miles since the last change), so I can't imagine the oil being thin enough to drop the pressure, but ya never know I guess.

Thanks!!!

[Mean Green]

I was told by the shop that changed my wife's that they are of poor design and tend to go out/leak a lot sooner than they should.

[scrisp2]

Originally Posted by Mean Green

I was told by the shop that changed my wife's that they are of poor design and tend to go out/leak a lot sooner than they should.

The oil pump or the sending unit?

[Mean Green]

Originally Posted by scrisp2

The oil pump or the sending unit?

Sorry, the sending unit. They are weak.

[scrisp2]

Originally Posted by Mean Green

Sorry, the sending unit. They are weak.

Whew, that's much easier to replace than the oil pump. :-) I was so worried when the light came on, of course I was something like 40 miles form home and my wife was working late that night.

Thanks for the help, I'm gonna change the unit out and see if that stops the problem.