wrong oil filter or could be a different weight of oil
If the light was on before you changed the oil and you now have the correct amount of oil, and correct viscosity, then it can be that your oil pump is defective. not putting out enough pressure. if you have an oil gauge, if that shows oil pressure is OK, then your light can be shorted out.
Have they checked the oil pressure sending unit? How about the wire leading from the unit to the gauge?
your oil pumps probably going bad
usually means cam bearings are worn, that is where oil pressure is built
What happens first? Pressure/Engine Dying? Has the oil always been changed? If not oil will form sludge, when the oil is finally changed, the detergent in the new oil breaks free the sludge which can get sucked into the oil pump intake. this would cause an immediate loss of oil pressure and engine issues. Thats been my experience with sudden oil pressure loss issues. Dan
You may be losing oil pressure because of a blown head-gasket. If you have a computer which alerts you to oil pressure or service soon after you just had it serviced you'll need to reprogram it
For me I think it was my oil pressure switch. I had the light popping up on occassion and then one day I had a low oil level light on. I wiggled the wire around the oil pressure switch and now both lights are gone. My oil was just changed so I know my oil was not low. Check your connection on the oil pressure switch I was going to throw a new switch in because they are cheap but instead just wiggled the wire it looked hard to get out.
the weight of oil that is in the motor...10w-30 is more than enough, if the oil was changed and say 20w-50 oil was put in then your oil pressure is going to be higher...the oil is thicker or heavier
My oil pressure gauge is dropping to o and the oil was just changed and is full. What could cause this
Install a manual gauge to actually read oil pressure
change the oil pressure senser in the front of the motoer on the bottom just did it on mine
The warning light can come on when it is time to change the oil. Your oil pressure and oil level can be at recommended levels when the oil needs to be changed.