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Don’t ignore these signs if you want your car to last. 

Quick notes

– Experts found these are the common causes of low oil pressure

– A car may turn off in the middle of traffic if it runs out of oil

– Diagnostics will tell you whether you need to spend time and money replacing the oil pressure sensor

Oil is an essential part of your car’s health. After all, it lubricates the engine to keep it running. It helps separate the heat from engine components. This keeps the engine components cool and working while driving. 

Engine oil lights indicate low engine oil levels or low oil pressure. If the oil light illuminates while driving, pull over immediately and turn off the vehicle. It’s important to pull over immediately because the engine may stop in the middle of traffic and refuse to turn over if it runs out of oil. 

Oil pressure gauge vs. warning light

Oil pressure gauges rely on pressure senders. The gauge changes its internal resistance as the oil pressure fluctuates. The needle on the dashboard moves when a signal from the sender is sent through wires to the gauge.

“Zero” readings while the engine is running above idle indicates the gauge is faulty, the oil level’s too low or the oil pump is broken. If the pressure relief valve near the pump and filter has become stuck, you may see very high readings after a cold start. Turn off the engine or the oil filter could burst.

“Exactly how oil pressure is measured depends on whether the vehicle is equipped with an oil pressure gauge or a warning light.” – Car Engineer, Mia Bevacqua

Even cars without a standard oil pressure gauge will have a warning light. It will light up if the oil pressure drops too far. 

Low oil pressure signs 

 Signs that could appear when the oil is running low. 

  1. Burning oil smell. Smelling burning oil inside the vehicle could indicate a leak, and that oil is dripping onto hot metal. Let the car cool down, then check your oil level. If it’s low, top it up, and consider having a mechanic investigate the source of the leak.
  2. Oil pressure warning light. The warning light is connected to a sensor that monitors the fluid’s level. The warning light will activate when the pressure reaches a certain point.
  3. Loud noise. When the engine is not getting enough lubrication, it may start to make loud clunking, knocking, and grinding sounds. This can cause the car’s rods to break. Clunking or knocking sounds may indicate a failing engine. Without proper treatment, the car can seize and break down completely.
  4. Overheating engine. Engine temperatures increase due to friction between metal parts. The friction from the metals can cause the engine to overheat. You should pull over as soon as possible if the engine starts to overheat. Wait for the car to cool down. Drive to a gas station or mechanic if no one can come and help you out, but not much further than that before dealing with the low oil. 

Common causes for low oil pressure

There are several reasons for low oil pressure

  1. Not enough oil in the engine. Evaporation, burning, leaks, and the age of the car can all cause drops in oil to the point that there just isn’t enough. Sometimes just checking regularly and topping it up is enough. 
  2. Old engine. When the engine is old, it will burn more oil. Check your manufacturer’s instructions regarding minimum and maximum oil levels, and when to have the oil changed.
  3. Too High or Low Viscosity.  Your system may indicate a loss of pressure if it senses that the car’s oil viscosity is too low or high.  
  4. Defective Oil Pressure Gauge. If you have confirmed that the oil level is correct and the engine is running with no unusual noises or high temperatures, the indicators may be defective

Reducing the Risk of Low Oil Pressure

Normal oil pressure may vary slightly in different vehicle models. When an engine is at operating temperature, a typical system pressure may fall within a range of 20 to 30 psi idle. When driving, it should range between 45 to 70 psi.

Exact specifications will be in the vehicle’s manual. In most cars, the pressure switch sends a signal when the oil pressure is below psi. When checking the oil pressure use an oil pressure gauge tester to check the lubrication system in the vehicle. It will inform you about the condition of the lubrication system generally, including the oil pump.

Check your manufacturer’s instructions regarding minimum and maximum oil levels, and when to have oil and filter changed.

 Using high-quality lubricants and the right viscosity grade will ensure oil pressure efficiency. Be vigilant about checking oil levels yourself, and keep an eye on your engine parts and garage floor or driveway for leaks. Also, watch for blue smoke emitting from the exhaust, particularly with high-mileage engines.

If you’re concerned about oil pressure sensor issues, consult a mechanic who will conduct an inspection and run diagnostics. 

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