Oil Pressure Sender location 3.1V6?

[pocket-rocket]

It wasn't my vehicles, hence the dino juice. Now had it been my car, yeah I would do the sale just for the oil and give the filter away on Freecycle or Craigslist, lol.

[elsmootho]

3.1V6 Oil Pressure Sender and oil pump failure

- Possible Theory's:

Failed backflow valve, this is a flapper piece of metal like a reed valve, it might snap off and flow upwards towards the center tube exit and block the hole but i didn't see any loose piece of sheet metal in the filter and why would it fail EXACTLY after i changed the oil?

Failed Bypass valve in the filter, i'm not sure how these work, but when the oil is cold and the pressure is high like higher rpm, oil bypasses the cartridge inside the filter, i still dont see how that could cause it.

Here's what i think, when you drain the oil, the sump pickup tube drains as well, when you refill oil you get a big airpocket in the sump tube between the oil pan and the pump. The pump impellers are sucking on air, there's oil on the opposite side of the impellers, but it can't force that oil, and the oil thats in the filter up to the block, the filter is also partially clogged because it's old & dirty, this backpressure wont allow the pump to suck the airpocket through
and grab new oil from the pan, the pump is caught in an unprimed state. Putting a brand new "EMPTY" filter causes an air pocket ahead of the impellers but reduces the backpressure and allows the air before the impellers to get pushed through. The filter is also clean making it easier for the pump to reprime.

What do you think?

I've seen something like this when i was repairing a well pump for my uncle in Gaspe about 15 years ago.

I would suggest if anything like this happens to anyone (it may even happen with a new filter) you can back off the filter a few threads, start the engine for a few seconds and wait for some oil to start bleeding past the oil filter gasket. Lesson to me, don't be cheap and spring for a new filter each time, although i only had about 3000 miles on this filter.

Thanks to all for your support on this...

[robertisaar]

wait....... so you reused an old oil filter?

[elsmootho]

Initially I just changed the oil, I didn't touch the old filter, my bad, but it only had 3000 miles on it i figured i'd catch it next time around, thats how i got into this mess, but the way i see it, this could happen even with a new filter. Crazy stuff... I'm glad my pressure is back, engine seems ok now...