1999 Cadillac Deville

Engine Performance problem
1999 Cadillac Deville V8 Front Wheel Drive Automatic

I had a oil change several days ago, and apparently the peoplr put the wrong type of oil in the car. It ran fine the first day but now the oil pressure light comes on and will not go off. I keeps saying Low Oil Pressure Stop Engine. I immediately changed the oil to a more expensive synthetic blend, but it still does the same thing. What is the problem?
April 1, 2009.

Assuming you have no engine noise to accompany the light, you may have a sensor that failed. Sometimes they also get oil in the connector due to a sensor leaking, and end up shorting. The sensor is in the oil filter adapter housing, and is easiest to access by pulling the filter adapter off the engine. If you can get it disconnected, and the light goes out, I would consider replacing it.

Apr 1, 2009.