Engine tap at start up with oil light.

[eicheldp]

I searched the forum but couldn't find this topic. My wife and I stopped for dinner tonight after an hour's drive and when we returned to the car I had a concerning event happen.

I started my 04 S and had a loud tapping sound occur with the oil light illuminated. I turned off the engine immediately and then turned on the ignition to look at the oil level. (It was full.) I restarted the engine and it sounded normal. I drove home (2 miles) and the car performed normally with no tapping or warning lights.

I just changed the plugs 90 miles ago and the old plugs looked normal. The Boxster has 33,700 miles on it.

Any insight into this would be appreciated. Thanks.