I have a 99.5 A4 1.8 T auto with 130K.I bought it with 127K Timing belt was done at 120K. The odd thing is, the oil light would just flash for a split second and go off. It usually happens with in the first 10 min of drive when I come to a stop light then I don't see it. Also I don't see it when the temp gets hot. I changed the oil at 130K with synthetic 10-40 oil and that's when I started to notice the oil light flickering. Is this a ground issue? Bad oil pressure sensor? Am I having real oil pressure issues? Is this a common problem?

TIA

Prasad