Electrical problem
1999 Saab 9-5 4 cyl Front Wheel Drive Automatic 127,00 miles

I own a 1999 Saab 9-5 SE and I have been having problems with the oil warning light coming on. About 3 months ago I took it into the shop to replace a loose chain and the oil light was going off at the time so they replaced the oil pump. I got it back and it ran fine for about 3 weeks and then spiratically at different times throughout the course of about a month it would go off at different times: only when the car would come to a complete stop though. Then it stopped for about two weeks and started again. I took it into the shop last week and they thought it was the oil pressure switch, so they replaced that and it didn't go off for two days and then yesterday it was going off every time I stopped. Yet, today it did not go off at all....Any ideas please let me know...