Deanyel, sorry to hear of all your efforts without resolution but (selfishly I admit) it tells me I may not need to bother with these items. Frankly from all I've read I've never come across anything that solved the problem directly.

I'm beginning to wonder too what is really going on if all the usual suspects are not the problem after all. Maybe its all about aging oil pumps? Perhaps these pumps work well enough during idle and drive time according to our dash gauge readings but tolerances are no longer adequate for the deamnds of initial initial start ups?

Anyone tried a new oil pump with good results?

Anyone have any insight into oil pump at all?

Process of elimination is expensive.