if the car sits for a couple days the oil bleeds out of the upper engine and when its started it knocks for a second or two. sounds like its coming apart until the oils pumped back through the system. the body shop guy said in some cars theres a small disc held by a spring in the oil filter housing the gets dirty and needs changed or cleaned. i cant find the shop manual where moving and its packed somewhere. can this be an easy fix.
thanks

i can tell ya that the oil filter housing on our engines is 2 pieces and i didnt see a spring in it when i took mine apart.
as for inside the oil pump housing :shrug i just bought a new one

and sitting a "few days" is this like over a weekend? or like you went on holiday for a week?

does the oil level change dramaticaly from when you park it to when you start it again?

does the sound stay in the upper valve train or does it sound like its coming from the bottom end as well?

my car did that after it sat for about 5 days, but it stopped after i drove it for 5 minutes.......

Oil will always bleed down after sitting. There is no check valve in our oiling assembly to prevent that, nor is there in any car I know of aside from the oil filter flaps or in some applications, a valve in the head. However, none of those solutions do anything to prevent oil from bleeding out where it's SUPPOSED to - past the crank bearings, which are the lowest point in the oil path. If you sit for more than ten to fifteen minutes, your oil galley is empty.

That's normal. You're looking for a culprit where none exists.

the problem is if i leave the car for 5 or more days without starting it. when its started it sounds really bad. its been at the body shop for the last 3 months and we started it every other day or so and its fine. but when we go on vacation and leave it in a month or so then itll happen. last time i tried poring oil in. but it needs to keep oil around the crank bushings. the cars been around so i know stuff is worn. is there and easy way to pre pressure the system or any fix short of a rebuild.

Do you have an oil pressure gauge? Did you actually catch a problem here, or you are just assuming the noise is because of low oil pressure?

Oil pressure that is below spec is caused by worn bearings. The oil pump flows oil, it doesn't create pressure. Bearing clearance determines the pressure.

Regardless, sounds like worn mechanical components. I'm sorry but, they make no additive that repairs engines.

I've experienced what he is describing. It only happened after the car sat for about 2 weeks without being cranked. I learned after listening to it knock for about 1 second after starting it to disconnect my coil pack to let it pick up oil pressure. I just chalked it up to having 140k miles on a motor.

heavier oil or an additive like Lucas or BG MOA might help but it's really just a band-aid fix, you're probably dealing with a little rod knock from worn components, might be time for a quickie "california rebuild", or a real "proper" rebuild. the full rebuild is the better way to go but I've gotten away with quickies before for a long time.