The oil pressure sensor is an important automotive component. As the name suggests, it's designed to sense the pressure -- as well as the level -- of engine oil. The oil pressure sensor will relay this information to your vehicle's electronic control module (ECM). There are instances, however, in which it can fail. Below are several signs that your vehicle's oil pressure sensor is bad.
#1) Oil Pressure Light Constantly Illuminated
If you notice the oil pressure light on your vehicle's dashboard is constantly illuminated, the oil pressure sensor could be bad. With that said, it's normal for this dashboard light to illuminate when there's a problem with the engine oil. If your vehicle has an oil leak, the engine oil pressure inside of your vehicle will decrease. The oil pressure sensor will detect this reduction of pressure, which it will use to trigger the oil pressure light.
Nonetheless, a bad oil pressure sensor may result in this dashboard light being constantly illuminated. Assuming there's plenty of oil inside of the engine -- you can check the dipstick to identify the current oil levels -- the oil pressure light shouldn't be illuminated. Constant illumination is a potential sign that your vehicle's oil pressure sensor is bad.
#2) Erratic Oil Pressure Light Behavior
Erratic oil pressure light behavior is another potential sign of a bad oil pressure sensor. What does erratic behavior mean exactly? It means the oil pressure light is behaving in unexpected ways. Maybe it's flickering, or perhaps it's staying lit for a few minutes, followed by turning off automatically.
Keep an eye on your vehicle's oil pressure light while driving. If you notice erratic behavior, you may want to replace the oil pressure sensor. It's an inexpensive part that's relatively easy to replace.
#3) Oil Leak
A bad oil pressure sensor may cause your vehicle to leak oil. Oil pressure sensors are connected to oil sending units. Therefore, they can develop leaks. If your vehicle's oil pressure sensor is leaking oil, you should replace it as soon as possible.
All combustion engines need oil. Oil serves several purposes, some of which include lowering the engine's operating temperature, wicking away debris and reducing friction. When the engine oil pressure drops, the sensor may detect it. A bad oil pressure sensor may result in the dashboard light being constantly illuminated or experiencing erratic behavior. Alternatively, it can cause an oil leak.