Here we’re going to discuss the following engine sensor: The oil pressure sensor (or oil pressure switch). We’ll go over the functions of the sensor and the common signs to look for with a faulty oil pressure sensor.
How an Oil Pressure Sensor / Switch Works
The main job of an engine oil pressure sensor is to keep track of the oil pressure in the vehicle and then transmit this information straight to the combination meter or the instrument panel.
If the vehicle has an electronic control module (almost all do), then the oil pressure switch will send this information to the module where it can be calculated.
After it is calculated, the information gets sent to the combination meter or instrument panel so that the engine oil pressure warning light or the oil pressure gauge can be activated.
Symptoms of a Bad Oil Pressure Switch or Sensor
If there is a problem with the oil pressure sensor, then this will usually activate the engine oil pressure light. It could also cause an inaccurate reading to be given from the oil pressure gauge. Below are the three most typical signs of a faulty oil pressure switch or sensor:
#1 – Repeated Blinking from the Oil Pressure Light
Sometimes if the oil pressure sensor is not working properly, there will be blinking from the low oil light on the dashboard. This could cause a driver to panic because they’ll believe that their oil levels are low, which would end up damaging the engine if it were true.
In order to determine if this is a real warning or not, you should manually check your oil level to see if it is low. If it isn’t, then it is likely you have a faulty oil pressure sensor and you need to replace it right away.
Related: Common Symptoms of Low Engine Oil
#2 – Wrong Reading Shows on the Oil Pressure Gauge
If you are driving an older vehicle, then it likely has a mechanical gauge that calculates the oil pressure. Whenever the oil levels are normal but the gauge is showing zero, this means the oil pressure sensor needs to be replaced because it is faulty or there is some type of connection issue.
If you are driving a modern vehicle, then your oil pressure gauge is probably electronic and transmits an electronic signal to get the reading.
Whenever an oil pressure sensor is not working properly in a modern car, it will cause the gauge to have strange readings or it will sit on full or zero. Check the wiring to the sensor and replace as needed.
Don’t assume your engine oil level is low without physically checking the dipstick. Otherwise you may end up with too much oil in your engine which can mean a completely different set of issues.
#3 – Oil Pressure Light Turns On
The best way to test if your sensor is bad is through the lights on the oil pressure gauge. If the low oil pressure warning light comes on when they engine’s oil levels are normal and your engine is running smoothly and quietly, then you likely have a bad oil pressure sensor. Anytime this sensor is defective, it will give you false readings.
If your oil levels are normal but you hear grinding, ticking, or other noises from your engine, you have an actual problem with oil pressure such as a faulty oil pump and the sensor is simply doing its job.
Eventually, these readings will go way beyond the normal specifications which will cause the warning light to turn on. At this point, you should replace your sensor in order to stay properly informed of your oil pressure level.