I recently went to service a KX91-3 Super Series excavator. I started the engine to warm it up and to move to level ground for oil drainage. About 15 seconds or so after starting the engine, I heard an audible alarm and looked down to see the "engine Oil' message on the screen. Even though I knew the oil level was sufficient I shut it down and checked anyway. I went ahead and moved it and changed the oil and filter as well as the air filter (all were quite past the normal interval). However, the alarm is still sounding with the message. I wonder if the oil pump is damaged in some way? Help!!!