Suddenly a flickering oil pressure warning light or a low oil pressure reading appear on your dash.
You never want to ignore an illuminated dashboard warning light, especially if it stays on.
Driving without the necessary level of oil under the proper amount of pressure can result in damage to your engine.
Before you go too far in oil pressure troubleshooting, it probably makes sense to double-check the oil level.
Oil Pressure Troubleshooting
The oil pressure warning light system receives its information from an oil pressure sensor threaded into a major oil passage.
Oil pressure troubleshooting should begin with knowing how the system works.
Inside the oil pressure sensor is a diaphragm that is grounded when there is little or no oil pressure.
Consequently, this is what causes the warning light to illuminate.
When the engine is running, the oil pressure pushes against the diaphragm and disconnects the ground turning off the light.
On more modern vehicles, the oil pressure sensor actually sends an oil pressure value to the powertrain computer.
If the oil pressure reading goes below a specified level, the powertrain computer triggers the oil pressure warning light. In some cases, it shuts down the engine in order to protect it mechanically.
Some vehicles are able to distinguish between low oil levels and insufficient oil pressure. This will let you know if the pump is malfunctioning or if you just need to add some more oil.
Below are the most typical symptoms of a faulty oil pressure switch or sensor:
- Repeated Blinking from the Oil Pressure Light
- The Wrong Reading Shows on the Oil Pressure Gauge
- The Oil Pressure Light Activates
If the oil level is between ADD and FULL, and the engine was running normally (no noise) after the oil pressure warning light came on, the problem may be a defective oil pressure sending unit, oil pressure gauge or warning light switch.
Testing the Oil Pressure Gauge-(Oil Pressure Troubleshooting)
- Test the gauge by grounding the wire that leads to the sending unit on the block.
- When the wire is disconnected from the sending unit with the key switch on, the needle on the oil pressure gauge should be either all the way high or all the way low. Grounding the wire should make the needle move to the opposite side of the gauge from where it was before the wire was grounded. If the vehicle is equipped with an oil pressure light, touching the wire to ground and then removing the wire from ground should turn the light on and off.
- If either happens, the gauge and wiring are good and the sending unit is at fault.
Oil Pump-(Oil Pressure Troubleshooting)
The oil pump supplies the oil needed to lubricate your engine when it is running. Oil pressure prevents metal-to-metal contact between the engine components. Although the pump is one of the sturdiest components in your vehicle, it is important to know the failing signs.
If the oil level is between ADD and FULL, and the engine was making noise when it was running, the problem may be a bad oil pump.
Testing the Oil Pressure-(Oil Pressure Troubleshooting)
Remove the oil pressure sending unit on the engine and connect a pressure gauge directly to the engine. Start the engine to see if the pump is generating adequate pressure. If oil pressure is within specifications (typically 10 psi for every 1000 rpm) the oil pump is okay. If pressure is less than specifications, the oil pump or engine bearings may be worn.
Other Possible Low Oil Pressure Causes
An engine depends on an oil filter to protect it against abrasions and wear. The job of the oil filter is to screen out solid contaminants from getting into the engine. These contaminants often include metal particles, carbon, and dirt. If they were to get inside the engine, they would cause damage to the engine. Your car will then start to experience problems as a result of this pressure change. This means you must repair the problem right away before it gets worse.
Oil Galleries in the Engine
The oil pan or crankcase is what stores the engine oil. The oil capacity for the majority of engines is between four and six quarts. The job of the engine oil pump is to pressurize the oil and then circulate it. Once the oil leaves the pump, it will go straight to the oil filter for cleaning.
All the clean oil will then pass through a series of passages until it reaches the crankshaft. With oil galleries in the crankshaft, the oil is able to circulate through all the bearing surfaces of the engine.
Conclusion-(Oil Pressure Troubleshooting)
In summary, the oil pressure warning device provides vital information to the driver. The oil pressure light on after oil change is a serious problem. It means that there is no oil flowing inside the engine parts.