low oil pressure warning but also hear engine tapping.
It could be a bad oil pump, plugged or collapsed oil filter, low oil level or worn engine. That tap you hear may be a rod knock, if so your engine will need a re-build.
The tapping confirms the warning is correct
Certainly the oil pump could be bad. If it was not serviced properly I would suspect a plugged oil pick up screen. I sure wouldn't run the engine till the problem is discovered and repaired.
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