My oil pressure light as come on what is the problem

Oil pressure sensor, or most likely, oil level sensor, either sensors, wires, or connections.

The low oil pressure warning lamp will illuminate anytime the ignition switch is turned to the ON position without the engine running. When the engine is running, the light also illuminates if the engine oil pressure drops below a safe oil pressure level. To test the system, perform the following:
If the oil pressure light does not work, perform the following:

1. Turn the ignition switch to the ON position.
2. If the lamp does not light, check for a broken or disconnected wire around the engine and oil pressure sending unit switch.
3. If the wire at the connector checks out OK, pull the connector loose from the switch and, with a jumper wire, ground the connector to the engine.
4. With the ignition switch turned to the ON position, check the warning lamp. If the lamp lights, make sure the oil pressure switch is properly grounded in the cylinder block, and if so replace the oil pressure switch. If the lamp still fails to light, check for a burned out lamp or disconnected socket in the instrument cluster.

To diagnose an oil pressure light that stays on, perform the following:

1. Check the engine oil level and top off as necessary. If the engine was 2 or more quarts low on oil, test start the engine after topping off the oil level and recheck the oil pressure light operation. If the light stays on, stop the engine immediately and go to the next step.
2. Disconnect the wire at the sending unit, then turn the ignition switch to theON position. If the light remains on, check the wire from the sending unit to the gauge for being shorted to ground and repair as necessary. If the light goes out, turn the ignition switch OFF and go to the next step.
3. Replace the oil pressure sending switch with a known good switch.
4. Start the engine and check the oil pressure light operation. If the light stays on with the engine running, stop the engine immediately to avoid severe engine damage until the cause of the problem can be determined.

WARNING
If the oil pressure light remains on while the engine is started, stop the engine immediately. Do not operate the engine until the cause of the problem can be determined. Operating an engine with low oil pressure will cause severe internal damage.

Possible causes for an oil pressure light to stay on are:


Pinched or grounded sensor wireDefective oil pressure sending unitRestricted or severely leaking oil filterExcessive internal engine bearing clearance.Insufficient or severely contaminated engine oilBlocked oil pump pickup screen or severely worn oil pump

Your oil light is not a level indicator, it is a pressure indicator. If your oil light is on with the engine running, it either means that you have a bad pressure sender or you have no oil pressure. I suggest installing a mechanical pressure gauge to verify if you do or do not have oil pressure. If with the mechanical gauge you do prove to have oil pressure then simply change your oil sending unit. But if you do not have oil pressure with the mechanical gauge, then you must drop the oil pan and find out why you have no pressure.

Low oil pressure could be the reason the oil light in your car will come on. Test your oil pressure. Without enough pressure, the oil will not reach necessary areas of the engine. The oil pressure sensor itself may sometimes become clogged with sludge from the engine, especially if the engine has not been properly maintained. A clogged oil sensor can give a false reading of low oil pressure, which will illuminate your oil light. So, check the oil pressure sensor light.

That could be from not having any oil pressure "oil pump failure, clogged filter, etc" or from a faulty oil pressure sending unit. More tests would need to be performed but is it really an oil pressure light or is it the change oil light. More info would be needed

Redi Hoxha

The oil light only detects loss of pressure not oil level. Your oil pressure sensor or switch monitors oil pressure in your engine. It sends these signals to the ECU and to your oil pressure gauge or warning light. Swap out the oil pressure switch.

As an aside, I worked in a place with artwork from a very accomplished Toronto artist who signed his artwork just 'HOXHA'.

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I think you have a suspect oil pressure sender unit. Replace it as they are cheap and need to be reliable and it will be cheaper than getting the oil pressure tested. If the light still stays on with the new sender you may have internal wear or a partial blockage. If the light stays on you need to have it urgently checked by a mechanic or you could risk serious engine damage.

It occurred to me that you may find it by unplugging wires on the few items under the hood which may appear they could be the oil pressure sending unit.

The light should go out when the wire is unplugged, and if it does it is bad. That's your continuity test.

If you unplug the oil pressure sending unit and the light does not go out, the cause of the oil light staying on is something other than the oil pressure sending unit.

RE pete cass posting: I believe that if the sensor is diconnnected, the oil pressure light will not light (at least because of the oil pressure sensor switch being disconnected) -- the symptom here is the light won't go off. The switch is closed with oil pressure below 10-15 PSI and open above that oil pressure -- this is a normally closed switch.

If the oil light is on it's one of 2 things: You have no oil pressure, or the sending unit (also known as the oil pressure switch) is defective and is reading no pressure when there actually is normal pressure. You should always assume it means no pressure, because driving it this way will ruin the engine.

This is the pressure light, nothing to do with the oil needing to be being changed, you have low oil pressure being indicated, this will destroy the engine if the light is really indicating low oil pressure, have the oil pressure tested with a mechanical test guage at a shop, if the oil pressure is ok then replace the oil pressure light sending unit.