It could be a failing oil pump. Lets see what Bill has to say on that. A bad cam bearing woudl slowly drop oil pressure and then loose it all together when up to heat. And you would hear a groan from the top end. A bad rod bearing might give a bit of a knock, and could explain the jumping oil pressure. Hover, if it'* a bad pump I believe I have 3 of them on the shelf. I can sell you the whole timing cover with pump at a fair price. Just swap them out. If it'* a bearing, then it'* time to look for a new engine or a new short block and transfer parts. But lost oil pressure is only a few things, bad pump, clogged filter, stuck relief valve, and bad bearings. Because you have noise the loss is real and not a bad sender unit.
SAVING THE WORLD ONE BONNEVILLE AT A TIME
1997,1998,2000,2005 year confused Bonneville SSExi. Stock? ish.
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