Leaking pressure switch
No one likes to see dirty oil dripping from under their vehicle, especially given the resulting unsightly mess left on the road. The owner of this 2004 Vauxhall Corsa was regularly checking the oil level and, up until the day the drip started, it was not using a drop. Once he had discovered the drip, the oil level started dropping rapidly.
Oil leaks can be difficult to find, especially if they have been present for a while. In those circumstances, the oil builds up and ends up coating the whole of the engine. As the oil leak on this Corsa was new and quite severe, we quickly traced the cause of the problem: the oil pressure switch had failed internally and was allowing a steady flow of oil out through the switch.
A new switch and a quick clean down of the area around and below the switch soon had normal service resumed.