Having good oil pressure is very important for the engine In order to minimize damage to individual components and the engine as a whole, as fast-moving metal surfaces create a lot of heat and friction and require continuous lubrication. 

Driving with a bad oil pressure sensor is not necessarily a very good idea as it prevents you from knowing if there is a problem with your oil pressure, which can hurt your engine and potentially put you and your car at risk. Although, if you absolutely have to, you can drive. But get it fixed ASAP as the longer you wait, the worse it can get.

The oil pressure sensor is there for a reason. It measures the internal pressure and sends a signal to the oil pressure gauge when it detects a problem.

Related: Is It Bad If Your Oil Smells Like Gas?

Signs Of a Bad Oil Pressure Sensor

When the oil pressure warning light comes on, you know there is a reason, but what if starts coming up at seemingly random times that just don’t make sense? How do I know if there’s is actually something wrong with the oil pressure sensor? We’ve compiled a bunch of signs to help you out with that question:

1. The Warning Light

Any time you see the oil pressure warning light come on, even if you know the sensor is bad, you still need to check it:

  • If the oil level is fine and the engine is running quietly and smoothly but your gauge says otherwise, then it’s probably the result of a bad sensor
  • If the oil level is good, but you hear loud ticking or grinding noises coming from the engine, this could mean that your oil pump isn’t working, or not working properly. In this is the case, do not start the engine until it’s fixed.
  • If the oil level is low, it could mean a lack of pressure from a leaking hose or gasket, or possibly that the oil is being burned in the combustion chamber, because you simply don’t have enough oil. In this case, you should stop driving as the engine can only work for about 30 minutes without oil before complete failure, but even if you drive for 5 minutes the damage could be major and very expensive.
  • If the oil level is high, the pressure relief valve near the pump and filter is probably stuck. The engine should be switched off as the oil filter could burst.

2. The Oil Light

Problems with the actual oil pressure in your car shouldn’t be intermittent, thus a sporadically blinking oil light is the clearest sign that the sensor itself is broken.

Although if you have a much older car, it might not have a dedicated oil pressure light and instead might appear as the “Check Engine” light.

But since not all check engine lights on those cars necessary mean there is something wrong with your oil pressure. It wouldn’t hurt to check the oil levels yourself, making sure it is adequate and there are no strange noises.

If your oil pressure sensor appears to be functioning, another reason your Oil Light may come on is if the oil pressure is low. This is obvious, but important to know.

Low pressure means that either the pump does not circulate enough oil (whether it’s due to worn parts, leaks, etc.), or there just isn’t enough oil to circulate.

Oil is important to keep parts lubricated, so if your oil pressure is low, you should turn your engine off and investigate, or visit a mechanic.

3. The Oil Pressure Gauge 

Just like the oil light, your gauge shouldn’t be intermittent, thus if you get a constant gauge reading of either very high or absolute zero, your sensor could be to blame.

Although it could be an internal short in the sensor, giving a constant high/zero reading, or damage to the wiring, a corroded plug, or simply an unplugged connection.

Before you conclude anything, you should test the oil using a dipstick and listen to the engine. If you notice too much oil, remove it immediately, as too much oil causes low pressure due to foaming, which isn’t good for your car.

A bad sensor can’t tell the true story of what’s really going on, so it is important to periodically check it, and replace it if necessary. If you need help with that, we’ve listed a how-to at the bottom of this article.

Related: Too Much Oil In The Car Engine – Signs & Solutions

How To Read An Oil Gauge

Oil gauges look like most indicators on your dashboard, but each car displays them differently. Some have a label with a number (could be “oil” “P” etc.) which ranges between 1-80 or 1-100 with an indicator needle.

While some have letters “L” “H” that indicates “Low” or “High” pressure, which is what we’ll be using in the picture below. If your unsure of which one you have or how to “read” it, check your owner’s manual or do a quick google search for more info.

Zero
This is normal only when the car is idling. If this reading happens at higher speeds, it could mean one of three things:

1) The gauge is defective
2) The oil level is too low
3) The oil pump or its drive is broken.

Another thing to keep in mind is the wiring, as damage to the wiring harness, a corroded plug, or simply an unplugged connection could be the culprit of the problem.

If any of the listed happens, turn the engine off and check your vehicle ASAP to avoid damage. If your oil is empty, fill it up beforehand to avoid unnecessary factors.
Low
If your oil pressure gauge is continuously showing a lower number (usually below 20 or in the lower quarter of the gauge), get it checked, it could mean 2 things:

1) There’s an issue with the gauge itself or in the instrument panel.
2) One or more engine component have worn down, creating a drop in oil pressure

Not having enough oil pressure can lead to major and expensive repairs in the longterm, so it’s better to replace it before it leads to expensive repairs.

Don’t worry if the reading drops by only 5psi or so during a long run in hot weather.

Make sure your oil pressure sensor is displaying everything correctly. If you need help with that, we’ve listed a how-to at the bottom of this article.
High
The needle on the pressure gauge should settle at the midpoint after the car has been running for about 20 minutes. If it settles toward the top of the gauge, it indicates high oil pressure.

Extremely high readings after a cold start could mean:

1) The pressure relief valve near the pump and filter is probably stuck. The engine should be switched off or the oil filter could burst.

How To Replace The Oil Pressure Sensor

Now that you understand the importance of an oil pressure sensor and why you shouldn’t be driving with a bad one. It is time to replace it.

An oil pressure sensor replacement is one of the easiest jobs for a DIY that can save you loads of money. This will fix the oil pressure light on your dashboard. The oil pressure sensor is sometimes referred to as an oil pressure sending unit. The particular oil pressure sensor that Is used in the video was about $10 at the local auto store. Online you can find them for as low as $5.

Step 1: Locate the oil pressure sensor:

  • The oil pressure sensor is often mounted in the engine block or the cylinder heads. But since there is no industry standard, the sensor can be mounted in any number of locations. A quick google search can help you find it

Step 2: Unplug the oil pressure sensor electrical connector.

  • Release the retaining tab on the electrical connector and gently pull the connector out of the sensor.

Debris can build up around the oil pressure sensor over time. So it may be required to push it in and out a few times to free up the plug while removing the connector.

If that didn’t help, It may be required to spray some lube to help remove the electrical connector. You can also use a small screwdriver to gently pry the connector free. Be careful not to damage the electrical connector while removing it.

Step 3: Remove the oil pressure sensor.

  • Loosen the oil pressure sensor with an appropriate wrench or socket, Once loose, it should be possible to unscrew it the rest of the way by hand.

Step 4: Compare new/old pressure sensor.

Make sure that the replacement oil pressure sensor:

  • Has the same size as the one removed. This is all determined by the internal construction, but the physical dimensions should be the same.
  • Threads-in in the same diameter
  • Has the same thread pitch

Since the oil pressure switch is placed in a position where the oil is pressurized, some type of thread sealant is usually necessary. There are many different forms of sealant available, just make sure to choose one that is compatible for use with petroleum-based products.

Step 5: Install the new oil pressure sensor

  • Thread the replacement into place by hand until you can no longer turn it by hand.
  • Finish tightening it with the appropriate wrench or socket.

Step 6: Re-apply the electrical connector

  • Make sure that the connector is properly applied, and that the retaining tab is engaged. 

Step 7: Check if it works

  • Start the engine
  • Check if there is pressure on the gauge or if the oil pressure warning light goes out

Since removing the oil pressure sensor will let a small amount of air into the system, it can take about 5-10 seconds for the oil pressure to build back up. If it does not, and the oil pressure light does not go out, shut the engine off immediately, especially if you hear weird noises.