High oil pressure in a vehicle may seem like a good thing after all, it suggests that the engine is getting plenty of lubrication, right? Not exactly. While oil pressure is essential to proper engine operation, too much of it can signal underlying problems that could lead to engine damage if ignored.
In this detailed guide, we’ll cover everything you need to know about high oil pressure, including what it means, common causes, how to diagnose it, and what steps you can take to fix it.
What is High Oil Pressure?
Oil pressure is the force that pushes engine oil through the passages inside your engine. That oil keeps everything lubricated, cool, and moving smoothly.
Proper oil pressure ensures oil reaches critical components like the crankshaft, bearings, and camshaft. Without the right amount of pressure, oil can’t flow where it needs to, and that can cause serious problems.
Most drivers know low oil pressure is bad. But high engine oil pressure can be just as dangerous. Too much pressure can stress seals and gaskets, hinder proper flow, and even damage your oil pump over time.
That’s why your vehicle’s oil pressure gauge matters – it gives you a real-time reading of how well oil is flowing through the engine.
What’s the Ideal Oil Pressure?
Normal engine oil pressure is typically between 25 and 65 PSI. This figure can vary depending on what type of vehicle you drive and the motor that’s installed. Either way, the right oil pressure is required to ensure that the lubricant reaches all of the internal components of the motor.
If the oil pressure drops below these specifications, it’s referred to as low oil pressure. Without the right amount of oil pressure, there will be a significant loss of power, as well as a possible burning smell. It can also lead to abnormal engine noises, as well as permanent damage to the motor.
When the PSI gets over the specified range, it’s known as high oil pressure. Typically, high oil pressure is the result of the inability of the oil to pass through the crevices and bores to reach all areas of the engine.
Again, this leaves the motor unlubricated, leading to serious wear from the friction that occurs. In either situation, it’s necessary to resolve the issue promptly if you want to avoid premature wear to the engine.
What Is Low Oil Pressure?
If your engine is experiencing low oil pressure, the oil might not be able to reach the areas of the engine where it’s needed for lubrication. Pressure helps move the oil through the narrow passageways in the engine, and a lack of lubrication can cause the engine to seize.
Reasons For High Oil Pressure
Your engine isn’t supposed to run under pressure that’s too high or too low. There are several possible causes for high oil pressure, ranging from minor maintenance issues to deeper mechanical problems:
#1. Contaminated oil filter.
The most common cause of high oil pressure is a dirty oil filter. Oil filters usually last about 3,000 miles, but as time goes on, dust, soot, and other small particles begin to collect inside. This causes buildup, and your filter will need to be replaced.
Solution: Change your car’s oil filter. You can replace your car’s oil filter at home by draining the old oil and lubricating the gasket, or, if you want to avoid the hassle, most auto shops will do it for about $35-75 (or around $125 if your car needs synthetic oil).
Signs: If your car has black or excessively dark exhaust smoke, it’s likely spewing contaminants from your dirty oil filter. Another common (and more serious) sign of a dirty filter is knocking sounds in your engine. If you hear banging in the car’s interior, pull over immediately. This means parts are starting to rub together.
#2. Blocked oil passages.
As oil flows through your car, it carries debris with it. Over time, this debris (usually a combination of sludge and carbon deposit) builds up and causes a blockage in your car’s oil pathways.
Solution: Clean your oil passages. Remove your car’s oil pan and use a brush to scrub and scrape away all the sludge and debris. Then, rinse out the remaining contaminants with about 4 US quarts (3.8 L) of oil or warm water and re-insert.
Signs: The most common sign of blocked oil passages is a sputtering engine. If you notice your speed and engine sound breaking up, it means oil is not being properly circulated due to some obstacle.
#3. Relief valve malfunction.
Relief valves are like engine safe havens; they provide places for fluid to flow when the pressure gets too high.
Usually, car relief valves open automatically when oil pressure reaches a certain level. However, if your relief valve has a broken spring, plug, nozzle, or is adjusted incorrectly, this can cause a failure, which means the oil pressure in your car will continue to build.
Solution: see a mechanic. Pressure relief valves are a super intricate part of your car’s oil pump, and every valve is different. Rather than gamble, it’s best to see a professional who knows exactly what part to repair or replace.
Usually, a valve just malfunctions from normal wear-and-tear, and the replacement part rarely costs more than >$200.
Signs: Since your car’s relief valve is meant to regulate oil pressure, any oil leakage is usually a sign of a valve malfunction.
#4. Mismatched oil grade and viscosity.
Motor oil comes in varying degrees of thickness. Thinner oils do well in colder climates and circulate through your car more easily. In warm weather, the car needs a thicker oil and more pressure to flow effectively.
Oils also have varying grades: synthetic, mineral, and blended. If you use an oil that’s incompatible with your engine, it can cause pressure to build and overheat.
Solution: Use a more efficient oil for your vehicle. Check your car’s manual and/or the API Motor Oil Guide to ensure you’re using an oil that functions well under your vehicle’s viscosity grade and performance level.
Signs: If your car has a bad fuel economy (you hit empty well before the manufacturer says you’re supposed to) or has a difficult time starting in cold weather, there’s a strong chance you’re using the wrong oil.
#5. Damaged oil pump.
Oil pumps are responsible for engine cooling and lubrication. If your car’s oil pump is old and its bearings (the parts that absorb the friction) are worn, it can’t properly lubricate the engine, which creates a high oil pressure condition and overheats your vehicle.
Solution: Check your oil pump with a pressure gauge. Before you fix your oil pump, you want to make sure it’s actually broken. Remove your oil pump from the oil pan (it’s usually near the top) and attach a pressure gauge. Compare the pressure gauge’s reading to the recommended numbers from your car’s manufacturer. If it’s too low or too high, visit an auto shop and order a replacement.
Signs: Oil pumps usually need replacing about every 5 years or 12,000 miles. Since oil pumps are more intricate and directly involved with the engine, you’ll likely see a “check engine” light come on if your oil pump fails.
#6. Defective sending unit.
Your car’s sending unit controls the oil gauge on your vehicle’s dashboard. If your sending unit has been damaged by high voltage, impact, a blown fuse, or false grounds, there’s a chance that your oil pressure is fine, but you’re receiving incorrect readings.
Solution: get your gauge fixed by a professional. Broken sending units are inconvenient, but not dangerous. Make an appointment with a mechanic, and they’ll replace it (sometimes for free, since sensors are usually covered under warranty).
Signs: You won’t be able to tell if your sending unit is correct or not, unless you check your oil pressure with something else, like a multimeter or test kit. However, if your “check oil light” blinks instead of turning on steadily, that’s usually a sign that something is wrong with the sensor itself.
How To Fix High Oil Pressure?
In many cases, the remedy for high oil pressure is easier than expected. Take a walk through these steps to see if you can resolve the issue yourself.
- Allow the engine to warm up completely. If you’ve just started the engine, it’s best to give it a few minutes to see if it regulates once it is warmed up.
- Check the motor oil you are using. If you have chosen the wrong type or viscosity for your vehicle, you want to change the oil and filter. Check the manufacturer’s recommendations for oil type in your owner’s manual.
- Change the oil and filter. If it’s almost time for the regularly scheduled maintenance, go ahead and do it now. You can quickly change the oil and filter at home for under $75 in most cases. Even if you want to save time and take it to the local lube, you will probably still spend less than $125.
- Clean the oil passages. If you think there’s a blockage or sludge buildup in the system, you can start by dropping and cleaning the oil pan. Use a brush and solvent to clean off any debris. You can also add a heavy-duty cleaning additive to the oil, as long as it’s recommended by the manufacturer. Follow all of the directions on the product you choose.
If these fixes don’t solve the problem, it’s time to get help from a mechanic. Testing the sensors and gauges can be a tricky process that’s best done with someone who has mechanical expertise.
If you want to attempt these fixes yourself, reference the information found in your service manual. However, as professional mechanics ourselves, we know the importance of getting this problem resolved quickly before major damage occurs. This is one time when it might be best to give in and let the local repair shop have a look.
High Oil Pressure Symptoms
Spotting high engine oil pressure early can help you avoid costly and potentially major repairs. Not every engine shows the same signs, but here are some potential high oil pressure symptoms to watch out for:
- Your oil pressure gauge is high, especially after the engine warms up.
- The oil pressure or check engine warning light comes on.
- You hear unusual engine noises like ticking or knocking.
- You notice oil leaks or spot oil pooling under your vehicle.
- Your engine feels sluggish or rough, especially during cold starts.
Why High Oil Pressure Problems Matter
Oil pressure problems can damage more than just the oil system. When the pressure is too high, it puts stress on the very parts the oil is supposed to protect. Over time, this can lead to:
- Blown gaskets or damaged seals.
- Oil pump strain or failure.
- Incomplete lubrication of engine parts.
- Full-on engine failure if ignored long enough.
If your car’s oil pressure seems off, it’s worth getting it checked to avoid preventable damage and further repairs.