What Causes Low Oil Pressure & How to Solve It

by Synthetic Oil | Last Updated: March 19, 2023

Most people understand that engine oil is a vital part of your car’s performance. Without motor oil to lubricate the engine, your car will not operate optimally—or at all. So what does it mean when your oil pressure gauge is reading low? Today, we are going to look at the causes of low engine oil pressure, as well as the steps you can take to solve the issue.

Keep in mind that low oil pressure can be dangerous, so you should never drive around for long if this happens to you.

**Note** – A quick hello to anyone reading this, I’m Alastair and this is my site Synthetic oil.me. I started this site to help people with their oil questions, and hopefully what you’re about to read will help answer your questions. This page may include affiliate links to the likes of Amazon, which if you make a purchase I qualify to earn a (typically small) commission. Don’t worry as this won’t cost you anything, the likes of Amazon pay any commissions. Thank you in advance for your support as this helps bring you more (hopefully) helpful content.

What is Normal Oil Pressure?

Ideally, your vehicle’s oil pressure should be between 25-65 PSI. At idle, your vehicle is going to be around 20-35 PSI, depending on the make and model. Trucks tend to have a slightly lower PSI than cars while idling.

What is Considered Low Engine Oil Pressure?

Anything below 20 PSI at idle or in motion is considered too low. Keep in mind that this “low” point is going to be different depending on the make and model of your vehicle. If you drive a truck, the low range may be anything from 24 PSI and lower. If you drive a smaller car, this number will not be the same. Check your owner’s manual for more information.

What Does Low Oil Pressure Mean?

Low engine oil pressure can mean a couple of things, but the most pressing issue is that your engine is not properly lubricated. Low oil pressure is a worrisome condition because it can damage your engine if it is not corrected as soon as possible. Your engine needs the oil pressure to be within the average range in order to operate optimally. The pressure ensures that the motor oil reaches every single nook and cranny of the engine, from the valves, bearings, camshafts, and other parts.

When the pressure is too low, the oil cannot make it through the engine. During operation, the moving parts will lack lubrication causing them to rub and eventually damage the engine, potentially even seizing up.

In short, low oil pressure means that your engine is not getting enough oil.

Symptoms of Low Engine Oil Pressure

How do you know that your car is running with low engine oil pressure? Here are some signs that you may notice:

1. The oil warning light or oil pressure gauge is lit on the dashboard. Once the oil pressure has hit a certain level, the light will switch on, warning you about an issue. Most cars these days have an oil pressure gauge as well that you can monitor.
2. Burning smell. Although low oil pressure does not usually cause oil leaks, it can cause a burning smell because of friction within the engine.
3. Decreased performance. Without oil to lubricate and disperse heat, your engine is going to be hindered. Not only that, but it will work harder and generate excessive amounts of heat.
4. Noise in the engine. If you hear ticking, knocking, clicking, or whining, the crankcase may begin to make sounds as it turns. Other parts of the engine may hit together, as well.

What Causes Low Oil Pressure?

If you are currently experiencing issues with low engine oil pressure, some of these factors may be the cause:

1. Low Engine Oil

One of the most common reasons for low oil pressure is that your engine oil is below the minimum amount. Low motor oil is problematic because it means that your engine is dry during operation. Make sure you are getting your engine oil and filter changed every 5,000-7,500 miles or every 3-6 months, depending on driving conditions. Without oil, your car cannot operate efficiently.

Furthermore, never go beyond 10,000 miles between oil changes. At that point, the oil may be too thick and sludgy to do anything but ruin your engine.

2. Wrong Oil Viscosity

Yes, oil viscosity is key in maintaining the health of your engine. If the engine oil is too thin, there will be less pressure, meaning that less oil gets through the entire system. As such, your oil pressure gauge is going to read low. In comparison, if you choose an oil that is too viscous, the resistance may be too high, leading to a lack of oil around the engine. This may cause low or high oil pressure. Again, the oil pressure sensor will go off, altering you.

Keep in mind that choosing the right viscosity is important. For example, while you can use 5w20 instead of 0w20 in most cases, you do not want to swap in a 10w40 when the engine calls for 5w20. Especially in the winter.

3. Damaged Engine

Let’s say you have checked the oil level and know that you just changed your motor oil. Why, then, is the oil pressure light still on? Well, not to be the harbinger of bad news, but it could mean that your engine is starting to wear down.

Engines do not last forever. There are multiple moving parts inside that start to break down, particularly once an engine is over 75,000 miles. One of the best ways to maintain the health of a high-mileage engine is to switch to high-mileage synthetic oil.

A damaged engine also includes worn engine bearings, which are another reason your oil pressure may be reduced. Oil flows through and around the bearings and crankshaft. In high-mileage engines, these pieces are worn, which increases clearance. Because there is an increased clearance, there is an increase in oil flow but a decrease in resistance. In other words, less pressure.

4. Failing Oil Pump

The oil pump is what regulates oil pressure. Should you notice a distinct drop in engine performance, as well as a spike in engine temperature, it could mean that the oil pump needs to be replaced.

5. Clogged Pick Up Tube

Another reason you are getting low oil pressure readings is that contaminants have accumulated in the pickup tube that connects the oil pump and oil pan. Should anything block the pipe, the oil will not flow, often resulting in a drop in engine oil pressure.

6. Defective Oil Pressure Sensor

If the oil level is normal and nothing else seems to be wrong, you may have a defective gauge. This happens as your car begins to age. Unfortunately, this is not something you can DIY; you will need an automotive technician to test the readings for correctness.

7. Oil Filter Congestion or Failure

The oil pressure gauge is located behind the oil filter and pressure relief valve, meaning that if anything is wrong with the oil filter, it is going to affect your oil pressure reading. You should be changing out your oil filter with every single oil change. Otherwise, the contaminants in the motor oil, including dirt, soot, and metal shavings will start to clog the filter. If there is congestion, the engine oil will struggle to flow, leading to oil starvation in the engine.

What About Low Oil Pressure When the Engine is Hot

You may be wondering, “But the oil pressure drops as the engine warms up! Why?” Well, the answer is simple. The oil in your engine becomes less viscous the warmer it gets. Part of that is why your oil pressure decreases the hotter the engine gets from running. However, if your engine oil pressure falls outside of the 20-35 PSI mark during idling, something may be wrong. Sometimes, if the light is on for oil pressure, the reading could be caused by an issue with the sensor.

However, you do not want to drive if your engine oil pressure is too low, because that can lead to all kinds of issues. Turn your car off, wait for the engine to cool slightly, and then check for any leaks or visible engine damage. If you cannot tell what is happening, head to the nearest and most reputable automotive technician you can find.

How to Solve Low Oil Pressure

Solving the mystery of why your oil pressure is low can be done in a couple of steps. First and foremost, check the oil you used. Is the viscosity correct? If not, you may need to do an oil change.

At home, you can begin by letting the engine cool for about 5-15 minutes before checking the oil level. Once the engine is ready, you can pop the hood and locate the dipstick. Remove it, wipe it clean, then dip it back into the reservoir. Check the oil level. If everything looks good there, you can move on to seeking out signs of damage to the engine. Is the oil old or low? Do an oil change and replace the filter while you are at it.

However, if you suspect that your low oil pressure is caused by something else, like a congested pick-up tube or a failing oil pump, you are probably going to need to rely on a professional. They will be able to conduct an engine diagnostic test for any malfunctions with sensors, as well.

Final Thoughts on Low Engine Oil Pressure

Low oil pressure is a dire issue for any vehicle because it means there is a shortage of oil in the engine during operation. If you notice that your oil pressure light is on, do not wait. Get to an auto body shop as soon as you can. Otherwise, your engine may end up damaged beyond repair.