how to fix low oil pressure at idle

One of the most important fluids that any engine needs is the motor oil. It helps lubricate the different metallic components of the motor to minimize, if not eliminate friction. This helps ensure optimum motor performance while also preventing overheating. It protects and lengthens the life span of the engine itself. The only way you can ensure that your engine stays protected is by having the right motor oil pressure. If you have low oil pressure, it can undermine your engine's performance and possibly cause damage to its components. In short, it can spell serious motor trouble in the long run. What can cause the pressure in this engine fluid to drop? How can you address such issues? These are what we are going to answer in this article.

young man checking engine oil level

Causes of Low Oil Pressure in Your Car

There are many potential causes of low oil pressure in a modern combustion engine.

Insufficient Amount of Motor Oil

You may laugh about it but this is one of the most common causes of low oil pressure. What happens is that some car owners may have forgotten all about the periodic oil changes as part of normal vehicle maintenance. They may have already lost track of when they last had an oil change. It is also possible that they don't perform regular checks of engine oil levels.

Another reason why you may have insufficient motor oil is there's a leak somewhere in the supply lines. This will cause some of the lubricant to bleed through these minute holes. Oil seals and plugs can also wear out, causing a loss in pressure. Older engines are also less efficient in burning oil. As such, if you have a car that's already two decades old, you might see that the motor lubricant takes a lot faster to use up.

Wrong Oil Viscosity

Another possible reason why you have low oil pressure readings is that you used the wrong type of motor oil. We are referring to the viscosity that the manufacturer recommends for your vehicle.

Low viscosity fluids produce less resistance to flow. The pressure sensor in the vehicle can interpret this low resistance as low oil pressure. If the oil has a higher viscosity than what the manufacturer recommends, then it can generate greater resistance to flow. This can result in inadequate lubrication of the different components of the engine. This also translates to low oil pressure.

Accumulation of Dirt in the Pickup

One possible reason why you may have low oil pressure is there's clogging in the pickup pipe from the oil pan. This is especially true if you have been religious about the scheduled oil change of your car and you've been using only the right viscosity of lubricant according to the manufacturer.

The oil pump draws lubricant from the bottom of an oil pan. There is a pipe that connects the oil pan to the oil pump. However, before the engine fluid gets drawn through the engine, it passes through a filter or strainer. Over time, it is possible that dirt, debris, and other gunk can accumulate in this part of the system. As such, there is not enough oil going up the pipe. This can result in low oil pressure.

Damaged Oil Pump

Pressure can also drop because the pump is no longer functioning as it's supposed to. The work of the oil pump is critical since it facilitates the movement of the motor lubricant throughout the system. Think of it as your heart. If your heart stops beating, then it would be impossible for the blood to keep on flowing. This can lead to a host of problems.

While the oil pump is not a human heart, its function is quite similar to that. Hence, when it gets damaged, you can expect the pressure within the oil passages of the engine to drop, too. Stop the heart and you also lose blood pressure or you have a drop in blood pressure.

There are many causes of oil pump failure. It can be because of incorrect installation in case you had it replaced already. Oil contamination and poor oil maintenance can also damage the oil pump. It may also surprise you to learn that insufficient amount of motor oil can also lead to pump damage. Of course, there's always the time and usage factor.

Internal Oil Leak

Any leak within the oil passages of the engine can also result in low oil pressure. Instead of circulating through these passages, the oil will seep through cracks or other miniscule holes in the engine. In other words, the fluid that's supposed to keep the motor well-lubricated escapes from the system.

Some of the more common causes of an internal oil leak include worn piston rings and worn valve seals. In some cases, if the valve guides have excessive clearance, the excess space can lead to a reduction in oil pressure. Modern vehicles also have a PCV valve for more efficient use of energy. Unfortunately, if this system fails, it can lead to an unnecessary buildup of pressure within the crankcase. This can push out the seals and gaskets, leading to an internal oil leak.

Engine Wear

We already pointed out that the older the engine, the more susceptible it is to low oil pressure. We also mentioned that older cars will often use up their lubricants a lot faster than newer vehicles. That is why the frequency of oil changes increases with vehicle age. If a new vehicle requires oil changes every 7,000 miles, an older vehicle may require oil changes as frequent as once every 3,000 miles.

The reason for this is simple: engine wear. Regardless of how tough metal is, it is still subject to wear. The effects of friction and heat plus the addition of chemicals can all lead to the premature wear of engine parts. For instance, camshaft bearings and crankshaft bearings can wear down with the passing of time. When this happens, the "holes" through which they insert can grow "wider". This allows lubricant to flow a lot easier, lowering its pressure.

Motor oil cap under the hood of a car

Problems with the Oil Pressure Gauge

Sometimes, there is nothing wrong with the oil itself. There is also no leak or damage to the other components of the engine lubrication system. The problem can be with the oil pressure gauge itself. Vehicle manufacturers install these devices to help monitor oil pressure. Unfortunately, some engine parts fail over time. You may already be driving with low oil pressure yet the gauge is not showing you. Or, it could also be the other way around. It may show that you have low oil pressure when the fact of the matter is that you don't.

Issues with the Oil Filter

If the pickup filter gets clogged, then you can have low oil pressure. Likewise, if there is an obstruction or blockage in the oil filter, then this will also result in a drop in oil pressure. The oil filter also contains a pressure relief valve. This helps ensure that the pressure within the system does not overshoot its higher limit. The problem is that this valve can also get damaged. If it does, then oil will be able to pass through the filter with relative ease. A faster, unimpeded flow will lead to a reduction in pressure.

Symptoms of Low Oil Pressure

Because motor oil is important in the optimum performance of a combustion engine, inadequate pressure can lead to a number of manifestations.

Oil Level or Oil Pressure Warning Light on the Instrument Panel

One of the earliest signs that you may have oil pressure problems is if the warning light on your instrument panel comes on. Modern cars already have this warning system wired to sensors in the engine oil system. If the oil pressure drops to a certain level, it triggers the sensor and activates the warning light on the instrument panel. If you see this, then it's often wise to bring your car to the service center.

Unusual Clunking Noise in the Engine

One of the most important functions of motor oil is to lubricate the different moving parts of the engine. When oil pressure is low, it may not be able to provide adequate lubrication to these surfaces. This can result in loud clunking, grinding, or knocking sounds. If you hear any knocking or clunking sound in the engine when you are driving, it may already be a sign that the engine is starting to fail.

Smell of Burning Oil

The characteristic smell of burning oil is often an indication of an external oil leak. If there are cracks in the hoses or pipes, oil can drip onto hot metal surfaces, causing them to burn and emit the characteristic smell. This smell is most obvious when you are driving and the engine is running. As such, the moment you notice this sign, you should pull over to the side of the road. Let your car cool down a bit before checking the motor oil level. You may see a lower-than-usual level of engine oil on your dipstick.

Poor Engine Performance

One of the desired effects of adequate lubrication is the reduction of friction between and among moving metal parts. By reducing or eliminating friction, the engine is able to generate power at maximum efficiency. However, if there is low oil pressure, then there is also a commensurate increase in friction. This results in increased workload for the engine. In other words, your engine will have to work harder, causing a reduction in fuel economy.

Engine Overheating

It goes without saying that a drop in oil pressure can lead to engine overheating. While it is true that this is a function of the cooling system of the vehicle, part of the function of motor oil is the elimination of friction. Whenever there is friction involved, you also have heat generation. As such, by reducing oil in the engine, you increase friction. This results in the generation of more heat which can lead to engine overheating.

car engine

Managing Issues of Low Oil Pressure

It is easy to see how low oil pressure can lead to significant engine damage. That is why it is important to address the different issues associated with low oil pressure.

Always check the dipstick to make sure that the level is where it should be. The dipstick contains a marker. The level of the oil should not be lower than the line marked as MIN for minimum. If not, then one can add an appropriate motor lubricant.

When adding or changing engine oil, it is imperative that you use only the viscosity rating that your vehicle manufacturer recommends. Do not pretend that you know better since automotive engineers designed the engine to work best with a specific level of oil viscosity.

Adhering to the recommended oil change schedule is also a must. Oftentimes, vehicle manufacturers provide you with two options. You can either look at your mileage or the number of months that has elapsed since the last oil change.

And when we talk about oil change, it is also crucial to replace or change the oil filter. This is already a standard. With each oil change, the filter needs replacement, too.

If there is a problem with the oil pump, then it is imperative to replace it with a brand-new unit. Depending on your vehicle model, the oil pump can be challenging to access. As such, a professional mechanic can help you remove the bad pump and replace it with a new one.

A faulty oil pressure gauge may require replacement. However, there are also third-party oil pressure gauges that you can install and connect to the system. If you don't know how, then it's best to have a professional do it for you.

External oil leaks are quite easy to fix as they may only require the replacement of hoses, pipes, and other fixtures. Internal oil leaks are a different matter. These will require more professional solutions that will cost you quite a fortune.

Low oil pressure may look like a not-so-serious problem. However, if left unmanaged, this can lead to serious engine damage.

Sources:

How Do Oil And Air Filters Affect Your Engine? – HowStuffWorks
How Dashboard Displays Work – HowStuffWorks