The oil light turns on when there is almost no oil pressure. Either the oil pressure sender is bad (or bad connection), or your oil pump stopped working. If your oil pump stopped working, then your engine likely would have siezed up within a few minutes of driving. You would have also heard some very disturbing noises coming from the engine.
I'm really curious about the timing. It may be possible that one of the mechanics accidentally knocked loose the connector on the oil sender. Also, keep in mind that the connectors usually have plastic tabs, and those tabs are easy to break.
If your car is still driveable, then your oil pump is fine. I'd check the connection, and by the way, I'd also take care of that oil pan gasket. They can only get worse.
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Monday, September 24th, 2007 AT 9:53 PM