I havn't used my saab 93 for about 4 weeks because of personal reasons but on using it again I find that the Oil Pressure warning light is coming on when below 1500 rpm. I have looked under the bonnet and have noticed that there is oil around the head but can't see a leak. It is the 2.2 TiD and is on a 53 Plate. It has done high mileage but is in very good condition. Is there any common faults that may cause this, or does this sound serious? Please help
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