Can I swap my 4 cylinder engine from a manual transmission into a car that has automatic transmission 4 cylinder.
Oil light flashing but I see no leaks in driveway
If there are no other symptoms, the most likely reason would be an oil pressure sensor failing. Have it replaced and all should be well once more. However if the oil level is low, top it off and see if it stops. If there is a knocking noise, this would indicate a failed oil pump.