oil light was on, when starting this morn

[losh1971]

Had a funny thing this morning, the oil light was on when I returned to my car after letting it warm up for 10mins. I shut it down and checked oil all good. Started engine again and it came on but was flickering. Shut down again and glanced over the engine. Started engine again and the oil light went off and didn't come back on at all on my 30km drive to work. There was no rattles during the light on or after I pulled up.
Any ideas? Did have a look at some old threads saying blocked pickup or cracked pickup pipe. Although I would have thought the light would not have turned off if the former was the case?
Yesterday I replaced the rad, removed and refitted thermostat and flushed cooling system but can't see this being related.

 

[someguy360]

Oil's too thick for the current winter chills?

It's possible excess coolant got in the oil pressure sender which is located pretty much directly under most of your cooling system components. I'd unplug the sender make sure the plug is clean and see how it goes from there. I've seen sensors get a iffy connection once they get wet between the plug and the sensor, worth a try.

 

[losh1971]

That makes sense as i did pour lots of water around there washing off the coolant from doing the flush. The heater return line was disconnected and water pumped in through the block, directly above the oil sensor. Water and coolant was freely flowing from the heater return line too, just above the sensor.

 

[BlackVXGTS]

+1 for oil pressure sender/sensor. Used to have the same problem after washing the engine of my VS Calais V8. Any water would evaporate once the engine was hot and the oil light went away.

 

[losh1971]

It happened again after work today. Pulled over and pull the plug, yep water inside. Pulled the plug back out at home and let it dry. All fine now. Thanks for the help boys.