Why does oil light stay on when oil level is okay?

Rod and main bearings are shot. Time for another engine, if you really like this old truck.

The light is activated by an an oil pressure switch. With the engine not running there is no pressure so it lights up. When the oil recirculates, the pressure increase and the light goes out. Locate yours and change it, they are fairly inexpensive. If it stays lit after a change it may indicate something more serious.

That depends on the type of oil warning light being displayed. There are 2 types of warning lights

1. Low oil pressure light which all cars have
2. low oil level light which some cars have.

Low OIL PRESSURE warning means the oil pressure is below minimum and when this happens there will be insufficient lubrication of many engine parts because sufficient oil cannot get to all parts of the engine it is required to lubricate. Until the cause is identified and rectified the warning light will remain. If you run your engine with low oil pressure you will cause expensive damage to internal engine components.

Low OIL LEVEL warning means the oil in the sump has dropped to a dangerously low level (which may be due to an oil leak or abnormal oil consumption by the engine.) This warning means the oil level needs to be topped up and the warning will stay displayed until you top up the oil. Running the engine with low oil will cause expensive engine damage.
Since it is a 2 minute job, Oil levels should be checked fortnightly as a minimum, together with radiator coolant and power steering fluid levels, if you run the car most days each week as most people do.

It is possible for a warning light to remain displayed when the cause has been dealt with because there is a problem with the sender unit. However it needs to be established with alternative checks that the problem has been fixed before investigating if there is a problem with the warning light itself.

Your vehicle may have an "oil level" sensor built into the oil pan. If so, and the sensor is bad, the dash will constantly tell you that the engine needs more oil even if it does not. Checking the oil with the dipstick, a minute after the engine has been turned off on level ground is always the best way to check your oil. Try scanning the vehicles computer systems to see if there are any fault codes. The warning light may also be on a timer that just needs to be reset. The "Check Oil" light should be separate from the engine oil pressure warning light. As long as the engine oil pressure light stays off, you should be ok. Checking the oil pressure with a manual gauge would be a good idea as well.

Hi John, The oil pressure warning light is indicating pressure not level. You say the warning light is on at all times and the engine is losing power? I believe you should have a compression test carried out on the vehicle. It seems highly possible there has been severe damage to the engine. Is the engine emitting any strange sounds? How long has the oil light been on? How often do you service the vehicle by replacing all filters and engine oil? What engine oil do you use? Regards John

It could be that your oil pump is going bad and not generating the correct oil pressure in the engine.

Try some thicker oil , you have a worn component inside the motor, there is not enough oil pressure when the car first starts does this happen at an idle in gear?.

It can mean one of two things. Either your oil level is too low, meaning more than 1 quart, or your pressure is too low. The first thing to do is check the oil level in the engine and top it up. If the light goes out after this then everything is okay. If the light stays on you should get the oil pressure checked with a mechanical guage to get an accurate reading.

Get this done as soon as possible. Manufacturers don't give you much room with these lights, when they come on you are very close to the engine meltdown point. Hope this helps.

Check oil level sensor, replace if necessary. also, does your engine knock or make a tapping sound?

if its a red light get it sorted if its a yellow light indicating low oil level the chances are you have a broken wire on the bonnet realease sound silly but it is a common problem check the wiring very carefully arond that area if need to follow it back from the bonnet catch and you will find it but you must check very crefully!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!