Why does my 350 knock for 3 seconds when I start it? Oil pump or worse?

That's the filter I have on my GS, the Pureone, yeah its smaller than the PF24 and larger than the PF47 but it seems to work well, and seems to be constructed very well

 

Thanks, I've decided that I'm just going to drive it, anyway. It holds 15 PSI hot, and runs up nicely when revved up, so I don't think it is sick.

 

Good deal

 

The problem is solved. I switched to a PF-24 Ac Delco filter and the problem has dissappeared. I will never put a Wix filter on another car again. This never happened before I put a wix filter on and it hasnt happened since I took the Wix filter off. The challenge would be to put the wix on again and observe the sound but Im convinced enought it was the Wix. AC DELCO only for me from now on. Thanks to all who posted.

 

I am glad i brought up the filter, and even more glad its now fixed!

 

For a bit more cleaning over a reg filter watch RockAuto ,
they often have the pricy Mobile 1 extended performance filters M1-203 for Buick 350 on sale cheap.

never went for the wix filter, to much like amsoil or them door to door vacuum cleaners, if its so great, it should be on every shelf like other parts. my 2 cents