First thing i tried was the gascap, i think that only effects 99+ models though, but it didn't have any effect on mine either way.

recently i had to change the gasket for the oilpan, to gain access they disconected the downpipe from the muffler, i was told that can come loose after having done this. Any possibility that is what is causing the light to come on like it is?

My guess is that it could be related to back pressure if that's the case, but i'm no mechanic so i could be very wrong about that.