Most people are already familiar with the simple truth that oil is the lifeblood of most vehicle engines. The only exception nowadays are electric vehicles, which rely on electrical power from their batteries. The traditional internal combustion engine, however, relies entirely on engine oil to function properly.
OEMs incorporate several important features and components that help us keep an eye on the oil level and condition in our vehicle. First there is the rod, which is the fastest and easiest way to check your car’s current oil level as well as its condition. But how can we get a good idea of the state of our oil when we’re driving? After all, we cannot stop to check the dipstick every few kilometers.
Two more critical components are the oil level sensor and the oil pressure sensor, both of which form the main focus of today’s blog post. Let’s start with some information about why your oil level and condition is so important.
Background: Importance of oil levels and condition
As we mentioned above, oil is the lifeblood of the engine and it simply won’t run without it. The oil cools and lubricates the many, many moving parts inside the engine as it runs. If you took the oil out, the engine would still physically start and run normally at first, but it wouldn’t be long before the friction and resulting heat would simply overwork the engine and ruin it permanently. This is called catastrophic engine failure and is one of the many problems that engine oil is designed to prevent.
To operate safely, every engine needs a certain amount of oil inside it at any one time. This is the oil level we are referring to. Oil levels can be lowered by oil leaks as well as oil burns that can happen when the engine is not in optimal condition. Over time, the oil also becomes contaminated by metal chips, dirt, gravel, and other things that the oil absorbs from the engine during operation. The filter removes most of these impurities, but eventually it gets to the point where it can’t. This is the point at which you need an oil and filter change.
Contaminated oil is more viscous and clogged with unsightly debris, which is why it becomes less effective as both a coolant and a lubricant. The oil level sensor and oil pressure sensor cannot tell us the condition of the oil, but they at least let us know how much oil we have and if it is moving at the right rate.
What is an oil level sensor? How it works?
The oil level sensor is a long, thin instrument that is installed vertically in the oil pan from below. It sits in the oil and continuously measures the oil level both in state and in motion. The way it works is quite simple in essence. If the oil level drops below a predetermined level, the sensor will signal the ECU to activate an oil warning light on the dash.
Most oil level sensors work using an electrical resistance method. The less the sensor is covered by oil, the greater the change in resistive value. More modern cars and luxury brands use state-of-the-art ultrasonic sensors with a piezoelectric transducer that sends pulses to the oil itself to receive echoes. This information is then sent to the ECU.
Some cars will have an additional restricted power mode that won’t even let you start the engine if the oil level is too low.
Symptoms of a Failing Oil Level Sensor
- Different reading for the dipstick
If you are warned of low oil levels, the best thing to do is to do a manual check using your dipstick. If you do 2-3 dipstick checks and they all seem to deny the oil level sensor reading, then it is likely that you have a faulty sensor.
- Oil warning light coming on and off sporadically
A real warning about the oil level should be a constant and consistent oil warning light on the dash. If the warning appears and disappears, only remaining for a short time, the sensor needs attention.
- The “Check Engine” (CEL) light comes on
If you see a CEL warning, one of many potential things could be a warning that the sensor is faulty and in need of repair or replacement.
What is an oil pressure sensor? Where?
The oil pressure sensor is located in your car’s engine block and monitors the rate at which oil is traveling to and through the engine. If the pressure is dropping, it could indicate all sorts of problems like oil leaks, bad crankcase, and so on. Loss of necessary pressure means that the engine is probably not getting all the oil it needs and will therefore suffer unpleasant consequences.
The location of the oil pressure sensor is invariably somewhere in the engine block, but its exact position depends on the make and model of your car. In most cases it is located near the bottom of the head, but it can also be installed directly on the head if the design allows. You can also identify it by having a block connector attached and either a single or a pair of thin wires connected to it.
Symptoms of a Failing Oil Pressure Sensor
- sporadic warning light
Similar to oil level sensors, the sporadic appearance and disappearance of the oil warning lights is the first and most common sign of a problem with the oil pressure sensor.
- Excess noise, but no warning
When oil pressure is low, it generates a lot of excess noise in the timing chain and the engine in general. If you hear this noise but don’t see the oil warning light, it could mean the sensor is faulty.
- Sensor oil leaks
The pressure sensor has oil leaking all the time, but sometimes the sensor can develop leaks through its threads or even through the body of the sensor itself.
Is it safe to drive with low oil level/pressure?
In a word, no. The oil has to be at the right level and move through the engine at the right pressure to do its job, which is to be the lifeblood of lubrication and cooling that prevents engine failure. It’s like asking whether the human body can function with much less blood or very low blood pressure. There’s a reason you shouldn’t drive after donating blood!
If you find that your car is leaking oil or exhibiting other signs of low oil levels or oil pressure, it’s best to call a mechanic to have your car towed to a shop for repairs.
Oil level sensor and oil pressure sensor – replacement cost
Replacing the oil pressure sensor is usually less expensive than replacing the oil pressure sensor. oil level sensor. According to numbers of repairmanyou can expect to pay $50-250 for an oil pressure sensor and $480-580 for an oil level sensor.