Burning oil questions

[EthanBuck]

Turns out my engine is burning oil and I may have run it very low but hasn't broken... over the weekend under load the oil gauge needle would stay constant but on idle It would shake violent had checked my oil low and behold low.
There is oil on what looks like outside the valve cover but not tons. So, I'm thinking and hoping it's just gasket and not a crack. There's no smoke excessive smoke though and oil on the ground.
SO before getting to spend on the fun stuff on cosmetics and suspension and possibly replace gaskets among other things my questions are the following..
Should I just replace the valve cover gaskets or should I buy a full gasket kit.
Should I go with Fel-Pro or Mahl gaskets.
I want to do a coolant flush eventually, but should I do it before I replace the head gaskets (if I do do the head)
I'm at 140k miles now with no known previous knowledge outside of the last guy hitting a deer and the truck running fine after should I replace the CPS.
And should I replace my PCV valve because I ran it so low as a just in case measure and do the same with the Oil pressure sender or just do one over the other?

Extra notes just in case;
2002 3.0 with flex fuel and to my knowledge hasn't been run on flex
Was just 700 miles to next needed oil change
Put 5W 30 to help Ish with the oil drink

 

[rusty ol ranger]

First thing i would do is replace the oil pressure sender and make sure the wire going to it is tight. My 97 460 did this and the sender wire was barely hanging on.

The oil pressure "gauge" is basically a glorified idiot light. It either shows "normal" oil pressure, or zero. Erratic behavior is usually the result of a bad sender or connection.


Besides that...i usually used the felpro rubber valve cover gaskets and have had good luck with them.

Running it "low" on oil (espicially a 3.0) isnt going to crack a block...unless a rod goes through it...in which case it would be obvious

 

[mc17eln]

I finished rebuilding my engine last November, only to find out it was losing oil this August. I have oil trace from both front and back of the engine, so I am fairly certain that it is the front and back valley seals of lower intake manifold. I bought and re-installed this set:

FEL-PRO-MS-95372-1

I was glad to also found and addressed the issue of cylinder head leaking coolant underneath the lower manifold gasket into the manifold bolt holes. This time around, I added a circle of coolant gasket seal (red) around the coolant channel on one side of the manifold gasket.

 

[Roert42]

The gauge is for Oil pressure, not oil level. Once it stops reading normal you have one of three options.

1. sensor circuit is just not working

2. you have no oil in the engine at all

3. your oil pump is not pumping oil

I would say that is in order of probability.

If the sensor looks like it is working you can test your oil pump with a gauge.

You unscrew the sensor from the block and screw in the mechanical gauge, crank the engine and you can see if what it reads. If you have oil pressure on the gauge, then you have an issue with the sensor.

Realistically, if you were running with no/ low oil pressure or no oil for an extended amount of time you would know by the sound of the rod knock and a spun bearing.