No Oil Pressure

[MooSSe]

My dash gauge is showing zero oil pressure. The engine runs fine and is not overheating so I figured the sending unit may have gone bad. I replaced the sending unit, and still no oil pressure. The check engine light came on once for a while and went off on its own, and now it is not coming on, even though gauge shows no pressure.

There is plenty of oil in it. Which I just changed about 800 miles ago.

Is there some way to test if the oil pump is working before I just buy a new one and replace it?

Oh, by the way this happened immediately after I just replaced the alternator. I was running on batteries only coming back from Houston to Dallas until voltage went down to about 10.5v. It started hesitating so I figured the fuel pump was starting to go in and out so I pulled over at a truck stop. They didn't have batteries so I had my son buy two new batteries and bring them to me at the truck stop. I put new batteries in it, drove home, replaced the alternator, recharged old batteries and put them back in, and then returned new batteries. That was an adventure. I don't remember the oil pressure showing zero prior to replacing the alternator.

What other options do I have on the oil pressure?

Thanks,
Randy

 

[Daw14]

Add a mech gauge

 

[BossHogg]

I had my son buy two new batteries and bring them to me at the truck stop. I put new batteries in it, drove home, replaced the alternator, recharged old batteries and put them back in, and then returned new batteries.

You used and then returned ... Wow, just wow!

 

[Sherman Bird]

You used and then returned ... Wow, just wow!

Yeah, my thought too!

 

[MooSSe]

You used and then returned ... Wow, just wow!

Yes, I was up front with them when I brought them back. I was prepared for them to tell me they wouldn't take them back, but they did. I told them they were in my truck for about 30 minutes, I topped off their charge and cleaned them up. I figured if they wouldn't take them back then I would have them sitting on my garage shelf until my current batteries died. They didn't give me all my money back though, they kept the $40 core charges.