Before anyone asks yes the oil level is at max and yes im using the appropriate synthetic oil viscosity.

I bought my car used.

Once in a while only at start-up for about 5 seconds the car displays the low oil pressure message and makes low oil pressure engine sounds.

Never happens on cold starts but its always at sort of warm start (temp gauge 1/4-1/8 way).

What could be causing this? once it goes away it doesn't come back until another random warm-ish startup.

Could id be some sort of valve for the oil pump that is failing and gets stuck closed or half open then pops open?

Could it be debris in oil pickup screen (or idk how its called) from switching to synthetic which tends to loosen buildup? maybe previous owner used dirty dyno oil?

Could it be a bad oil pump?

Help would be greatly appreciated gonna take it to my mechanic but wanted some suggestions to help him out since its not a known problem.

THANKS!

edit: out of the 4 times that it has happened 2 times has been in a slope win which the nose of the vehicle is raised. This times it has sounded louder.

 

I'd first lean on the oil level sensor or "float" mech being faulty.

But first thing first, remove the oil filter and check the filter media for metal particles (aka, bad bearings).

Good luck!

 

thanks

it indeed has low oil pressure for a few moments at startup because i can hear the lifters clicking because of the low pressure.

I doubt it has bad bearings that would usually cause low oil pressure after running a while fully warm not at startup and fade, which leads me to believe that its a problem with oil pump or oil pickup screen.

besides i wouldn't jump to that conclusion before checking the simpler/cheaper options

any other suggestions from experience would be appreciated not just general knowledge

will keep updated once mechanic checks the oil pickup screen and oil pump rotary assembly also replace and inspect oil/filter