Low Engine Oil Pressure (Causes & Solutions)

Are you worried that your car may have low engine oil pressure and want to know how to diagnose this issue? If diagnosed, what should be done about it?

To answer these questions, this guide aims to give all the information you need about low engine oil pressure.

Low engine oil pressure can harm different components of your engine, thus creating trouble for the car. It is, therefore, necessary that the right oil pressure for your vehicle is maintained.

The symptoms of this problem are an illuminated oil warning light, diminishing engine performance, burning oil smell, engine noise, and engine overheating.

This article will discuss the causes of low engine oil pressure, its symptoms, how the issue can be fixed, and how its risk of occurrence can be reduced.

Let’s get started!

Let’s discuss further to know the cause of low engine oil pressure, its symptoms, and how to fix this issue.

What are the Causes of Low Oil Pressure?

When you have low oil pressure, it means there is a malfunction somewhere. It also means there likely is not enough lubricant moving through the system.  Bear in mind that lubricant deprivation will result in metal-to-metal contact and machine failure.

1. Oil Filter Is Obstructed

When oil goes out of your oil pump, it first passes through your oil filter. The oil filter prevents contaminants such as debris, from gaining access to your engine and also keeps the engine clean.

The filter naturally generates an obstruction in the oil flow, but it isn’t disruptive. The restriction in the oil flow will increase, as the debris build-up grows. This could eventually cause a completely obstructed oil filter, and fully hinder oil passage.

Your pressure relief valve would then open, to prevent blockage. This valve automatically opens, when pressure is greater than a pre-established value. Oil will then disregard the filter so that it won’t stop flowing. This detour will reduce the oil pressure to that of your bypass valve.

2. Dirt in Oil Pump

Oil is taken by the oil pump from the oil pan’s bottom, and the oil under pressure is circulated to the engine’s pistons, camshaft, and bearings. If there’s dirt in the pickup, the filter will prevent it from entering the engine oil pump. If the oil filter is filled up with debris, enough oil won’t be able to flow through it, until it is properly cleaned.

Excessive clearances may also be present inside your oil pump. If so, the pressure and flow will be reduced, because your oil pump’s ability to pump efficiently will be reduced.

This can occur because the only engine component lubricated using unfiltered oil is the oil pump because the filter is located after the pump. The engine oil pump may be damaged, if your oil pickup filter doesn’t seem to have any problem.

3. Defective Oil Pressure Gauge

If your oil pressure warning light is illuminated. Still, you’ve confirmed that you have a correct oil level, and your engine is functioning as it should without high temperatures or unusual noises; the issue could be a faulty sensing unit.

You might wish to test your oil pressure, using a gauge. Change your oil pressure sensor, if the gauge records a normal pressure level. However, if the low gauge reading or illuminated warning light continues even after you replace the sensor, the issue is likely a faulty oil pump.

4. Engine Bearings Are Worn Out

The oil pressure is generated through the resistance and flow that the oil produces, not the oil pump itself. The oil’s resistance is accumulated by the engine openings, which the engine oil passes through, and also through the amount of clearance between the crankshaft journals, and bearings.

Especially in an engine with high mileage, the amount of clearance will increase, because these bearings will wear down. This increased amount of clearance will result in a decrease in pressure and an increase in flow. An increase in engine pounding and noise will also indicate increased bearing clearances. If any other place in your engine has increased clearances, it may also decrease oil pressure.

5. Leaky or Weak Oil Pressure Relief Valve

The oil pressure relief valve aids in regulating the oil pressure and prevents damage to your engine, caused by a high engine oil pressure. When an initially set value is exceeded, the valve usually opens automatically. If dirt gets stuck, it may be because the relief valve is held open. This reduces the oil pressure.

6. Oil Level Is Low

If the oil level is low, your oil pump may draw air from the sump. This could result in the oil becoming aerated, and turning into foam. The oil will have reduced lubricating properties and excessive oxidation if this happens. An insufficient level of oil will result in your oil pump being unable to generate sufficient pressure. During high-speed turns, this low oil pressure may also fluctuate. The oil moves to the sump’s side during the high-speed turns, away from your oil pump.

7. Viscosity of Oil

An oil with low viscosity will flow through your engine more easily, than one with high viscosity. This is because less resistance is generated by oil has low viscosity, thus resulting in low engine oil pressure.

Temperatures impact the oil’s viscosity. If you use a mono-grade oil, you must consider the outside temperature when choosing the grade. This means that, if you’re using oil with high viscosity in summer, it would be better to switch to low viscosity oil in winter, to avoid using too thick oil, to flow easily.

This also applies when you’re using oil of lower viscosity in winter. It would be better to switch to high viscosity oil, during the summer to generate more resistance. A multi-grade oil can be used in all seasons, so it does not need to be changed based on the outside temperatures. Always adhere to the manufacturer’s recommendation, to choose the right grade type.

Also Read: Oil Pan Replacement Cost

8. Pump Wears out

If your engine is operating noisily, but the dipstick’s oil level is between “full” and “add,” you may have a worn oil pump. If your pump is worn, it will not be able to produce the required pressure because of internal leaks. Until you fix the issue, stop running the engine. You will need to replace the pump.

9. Leakages

The oil in your car will eventually be emptied if it is leaking. As a result, the car’s lubrication system will have a low engine oil level.

There are two common types of oil leakage, usually observed. These include a leak in the oil filler cap or valve gasket, or a leakage in your oil filter or oil pan, which oil drops below the car can usually detect.

There are various places where there can be oil leakage. Wherever you locate it, it needs to be fixed without delay. In a best-case instance, a defective drain plug or your oil filler cap is the issue, which can easily be fixed by changing them.

It may also be that your oil pump has an internal leak, leading to reduced oil pressure even when your oil level is adequate.

Signs of Low Engine Oil Pressure

1. Declining Engine Performance

You might be experiencing a diminishing engine performance, if you are suddenly stalling out, losing power, or burning through the fuel tank faster. Although this drop may indicate various car issues, it is commonly caused by low oil pressure. Therefore, start small by checking your engine oil level, because you may just need a filter and oil replacement.

2. Oil Warning Indication Light

Your sensor might activate the oil warning light on your dashboard if the pressure of your oil goes below an adequate level. If the light illuminates, pull over to a safe area – ideally a gas station, service station, or parking lot – and check the oil level. If you have an appropriate oil level, getting the car towed to an auto repair shop would be best. The problem may be that you have a defective oil pressure sensor, or a larger issue could be the case.

3. Burning Oil Smell

If your car has an oil leak, it may be indicated by the smell of burning oil, and the oil may be in contact with the hot surface of one of the components within your vehicle. This smell usually indicates an oil leak, which may cause a decrease in oil pressure. If you perceive burning oil when you’re driving, locate the nearest parking lot or gas station and pull over, so you can check your engine oil level.

4. Engine Begins to Overheat

The engine oil lubricates the moving parts of your engine. If the oil pressure is insufficient, your vehicle’s engine will function with increased friction and decreased lubrication, resulting in higher heat levels. Engine overheating could be a complicated issue. Although it does not always imply low oil pressure, the engine can overheat because of low oil pressure. If the engine is overheating, the engine components will experience stress and wear.

5. Engine Noise

If you have low engine oil, the components of your engine will not receive the required lubrication to operate properly. When this happens, knocking, clunking, grinding, or ticking noises may be heard from your car’s engine. In this case, you need to have your vehicle serviced as soon as possible, by a certified technician.

Relevance of Oil Pressure

Oil pressure is a very important factor, contributing to a long engine lifespan and the engine operating smoothly.

Engines are very complex machinery pieces, and they pull a lot of weight. Oil is necessary for the engine, to ensure that each moving part is properly lubricated and can function optimally.

Pressure builds up in an engine when oil flows through it. This pressure ensures that the engine oil gets to everywhere it’s supposed to and continues flowing.

If this pressure reduces to a point, where engine oil no longer flows freely to all the moving parts of the engine, the metal surfaces that aren’t lubricated will make contact with each other.

This will result in seal breaking, warping, friction, and other problems. In short, it is a fast way to damage an engine. Engine oil issues can cause serious damage to a vehicle if they aren’t resolved.

So, you must monitor your car’s oil pressure gauge, and carry out routine maintenance. You should stop your car without delay if your warning light illuminates to indicate that you have a pressure problem.

How to Control Low Engine Oil Pressure

Several crucial factors determine the engine oil pressure, which include oil supply, engine condition, engine oil type, the weather, and the condition of the oil pump, to mention a few. The following are some possible ways the issues related to low engine oil pressure, can be fixed.

Check Oil Supply 

If your oil pump isn’t receiving enough oil, it is only logical that your oil pump will be unable to generate sufficient pressure, in your engine’s lubrication system.

There will be engine sludge stuck everywhere, which could easily gunk up your pickup tube screen, starving your oil pump and every other part of the engine. Engine sludge occurs due to a lack of proper maintenance, but it may not be sufficient to carry out last-minute engine maintenance, to resolve the issue. Instead, you will most likely have to disassemble and clean the engine.

A plugged or faulty oil filter can restrict oil flow to your oil pump. Replacing your oil filter may fix this problem if there seems to be no other issue.

Watch Out For Wrong Oil Viscosity

If you use an oil having low viscosity in the winter, cold-start lubrication will be improved. Still, in the summer, with the hot engine running conditions, the oil will be way too thin, causing low engine oil pressure, as well as possible damage to the engine.

At your next engine oil change, it is possible that your vehicle’s recommended oil blend won’t be available, and another oil might be used as a substitute. If you are experiencing problems with low engine oil pressure after a seasonal change or oil change, replacing the oil with oil having the right viscosity might solve the problem.

Some cars may specify distinct winter and summer oil blends. Ensure that any engine oil change service is completed with the correct oil, before changing seasons.

Engine Issues

The oil pressure in new engines with very tight oil clearances, as low as 0.002 inches, will be at the highest possible value. This is because the restriction determines oil pressure and flow, all things equal. The miles the engine racks up will increase the bearing clearance, especially at the engine’s rear end, opposite your oil pump. This increased bearing clearance will increase the speed of oil flow, thus reducing pressure in your entire system. Similarly, oil pump wear may reduce pressure before the pressure enters the system.

In this instance, the engine oil pressure can be fixed using oil with higher viscosity, such as changing to 10W-30 from 5W-20. This oil viscosity change can return the oil pressure to its normal level by compensating for the increased bearing clearance.

This type of engine oil pressure issue can best be fixed, though, by repairing the bearings. When an engine is rebuilt, the oil pressure can be restored by using thicker bearings to reduce clearance.

Oil pressure in your pump can be reduced by oil pump wear. You could resolve this issue using oil with higher viscosity, but it is better to replace the oil pump.

Identifying a faulty oil pump drive belt or oil pump shaft may be more difficult because it requires some disassembly. Replacing the defective parts is the only method that can be used to resolve this issue.

Electrical Issues

Electrical problems may result in erroneous meter readings or warning lights if your actual engine oil pressure doesn’t have any issues.

Faulty engine oil pressure sensors, also known as sending units or pressure switches, are common points of failure, continuously under pressure in a very hot environment. Following your vehicle’s repair manual, use a digital multimeter (DMM) to check your sensor when your engine is running, after you have verified the actual pressure using the tool.

Open circuits and short circuits may also cause inaccurate pressure warnings. Use a repair manual and DMM to locate the circuit that needs to be repaired.

Watch the video below to learn more.

Controlling the Risk of Low Oil Pressure

The filter and oil should be changed at the right intervals, to minimize the risk of your engine having low oil pressure. Also, use lubricants of high quality, as well as the correct grade of viscosity, and proper quality standard as specified in your car/engine manual by the API (American Petroleum Institute).

Inspect the garage floor (and engine) for leaks, and check your oil level regularly. In addition, be on the lookout for any blue smoke that emits from your exhaust, especially in high-mileage engines.

If your pressure sensor comes on and you’re not aware of the exact problem, don’t drive the car. The best proactive/predictive strategy for fleets to know the machinery, and oil condition is to employ oil analysis.

Also Read: Car Blowing White Smoke After Oil Change (Causes & Fix)

Frequently Asked Questions – Low Engine Oil Pressure

Conclusion – Low Engine Oil Pressure

You will notice an oil gauge drop, or an illuminated warning light if there is any problem, notifying you of low oil pressure. You must stop immediately and turn off the engine, to avoid any damage.

Regular maintenance can prevent most oil pressure and other automotive problems. This includes replacing the engine oil and engine oil filter at regular intervals, determined by miles driven or a set duration.

The old favorite saying, “working like a well-oiled machine,” is also applied to internal combustion engines. You will experience many comfortable and safe miles with your car if you have an adequate oil level.

Ensure that your vehicle always has the required engine oil level. The right oil for your particular vehicle, having proper viscosity and adapting to your climate, should be used.