The engine lubrication mechanism works to supply automobile oil to the moving parts of the power unit under pressure created by the oil pump. If for various reasons a drop in engine oil pressure occurs, the lubricant will not be able to reach all parts of the unit, which can lead to its breakdown. Therefore, to constantly monitor the level of lubricant pressure, a sensor (light) is located on the dashboard of the car, which, in the event of a malfunction, sends a signal to the driver.
If the oil pressure light comes on while the engine is warm, the driver should quickly stop the car and take all measures to eliminate the problem.
What happens when the oil pressure light comes on on a warm engine?
If problems arise with the pressure level, the engine begins to experience the following problems:
- lack of lubricant;
- wear of moving parts increases;
- the heating of the engine as a whole increases;
- engine cleaning from soot and various deposits is reduced;
- malfunction with subsequent breakdown of bearings;
- Noise in the engine housing increases.
All of the problems listed above ultimately lead to jamming and engine failure.
When can it light up on a warm or cold engine?
It happens that when you start the engine, the LED lights up and does not go out, or blinks regularly. With a warm engine idling, the pressure lamp will light steadily in the event of a breakdown. In fact, the control light is not an indicator of excellent quality of the smear and the presence of a sufficient level of the substance within the system. The main task of the sensor is to record the pressure level and lack of lubrication in the system. In other words, the LED will light up if the pressure in the system drops below a critical level.
It should be noted that short-term lighting of the light bulb (within a few seconds) is allowed. This happens before the engine starts and is normal. The oil pump should not maintain the required level, therefore, after turning off the engine, there is no pressure in the system. The required voltage appears after the starter begins to crank the crankshaft. Now, if after this the light does not go out and continues to blink, then it’s time to start looking for the cause of the malfunction.
It should be added that when the vehicle is stopped, the oil in the crankcase thickens (especially mineral water) and the oil pump needs time to increase the pressure level.
Diagnosing oil pressure problems
Checking the engine oil level . The cause of the problem may be a small amount of lubricant in the unit.
The reason for the decrease in level may be:
- through damage to the oil pan;
- increased engine consumption due to severe wear;
- increased oil consumption due to waste;
- wear or improper operation of the oil pump.
Having such problems, you need to immediately tow the car to the nearest service station to eliminate the above problems.
Simply adding oil to the required level will not solve the problem. Replacement with lubricant of optimal viscosity . Each brand of car has its own brand of lubricant that must be used during its operation. For example, using 0W20 oil instead of 5W40 leads to severe dilution of the lubricant, since the lubricant used does not comply with the car manufacturer’s recommendations in the manual. This situation can lead to leaks of engine gaskets and seals, which is guaranteed to lead to a decrease in the engine oil level and a drop in its pressure. To avoid getting into such a difficult situation, you need to carefully select the viscosity indicator and other main indicators.
Good to know: Is it possible to add oil to an engine of another brand?
Timely replacement according to the kilometers traveled. It is important to remember that oil may simply lose its protective properties after a certain period of time. It is recommended to replace it after 10-14 thousand km.
Good to know: When should you change the engine oil based on mileage or once a year | How long does it take to change the engine oil
Undesirable mixing with antifreeze. Such troubles can arise from cracks in the cylinder block or from a breakdown of the cylinder head gasket. When antifreeze is mixed with oil, the chemical properties of lubricants change and deteriorate. The first sign of such problems is the presence of an emulsion on the surface of the oil dipstick.
Fuel getting into the engine oil. This problem can arise when the ignition and subsequent combustion of fuel in the engine cylinder is disrupted. As a result, fuel gets into the oil, which greatly dilutes it and leads to a drop in lubricant pressure.
Excessive abuse of various additives. Adding various additives to the oil can also lead to a loss of lubricant quality and ultimately lead to problems.
Good to know: Which motor oil is not counterfeited in Russia, list of the best
Wear of various engine parts. This situation may be caused by an increase in gaps between parts, resulting in a drop in engine pressure and excessive consumption of lubricant. Such problems need to be solved only with the help of a major overhaul of the unit. Various additives will only alleviate the situation temporarily.
Oil receiver filter clogged. If a sufficient amount of lubricant does not pass through this element, the engine will begin to feel a lack of lubricant with all the ensuing negative consequences. The filter may become clogged due to the fact that various types of contaminants have accumulated on the walls of the pan. To solve this problem, you need to clean the oil receiver filter from dirt, thereby solving the problem of engine oil passing through it.
Timely replacement of the oil filter. If the filter is not replaced with a new one in time, it may become clogged and this may ultimately cause a drop in pressure levels. In addition to clogging, the oil filter may be of poor quality, which will negatively affect the operation of the engine lubrication system.
Good to know: Do I need to fill the filter with oil when changing the oil?
Irregular operation of the pressure relief valve. The valve, by its design, remains closed until the pressure exceeds the required norm. But if the valve sometimes sticks in the open position and then it is impossible to obtain the required pressure.
Oil pump failure. If this element breaks down, it must be quickly replaced or repaired. After all, without proper and constant operation of the oil pump, it is impossible to ensure uninterrupted and high-quality lubrication of all rubbing engine parts.
Possible reasons why the oil pressure sensor lights up
The problem is very common and can occur at any time. Drivers often show disdain when the sensor light comes on. For some reason, motorists think that this is a malfunction of the LED and do not take any measures.
In fact, if the light comes on, it means there is a violation and it is important to take quick action. First you need to determine the reason why the malfunction occurs. These include:
- malfunction of the oil pressure sensor;
- low quality of filled oil lubricant;
- inconsistency of the lubricant composition with the tolerances for a particular engine;
- a decrease in the level of lubricant as a result of a leak or increased consumption, for example, the lubricant is wasted or there are problems with the rings or valve stem seals;
- according to its characteristics, the lubricant is not suitable for use - the viscosity level is too high or too low;
- the oil pump is faulty or its performance is reduced;
- the oil filter and channels are clogged with deposits, as a result, it is not possible to create the required level of lubrication in the system.
From the above, it is important to take into account one thing - when the emergency pressure reduction light comes on, it means that the problem is obvious and needs to be solved. There is one significant point - the sensor can light up “cold” or “hot”.
Level above normal
Well, what if the oil level is higher than normal? Here the reasons should be sought in a different direction. Most likely, the viscosity of the lubricant will also be lower than that specified for engine operation. So what could be the reason?
One of the probable reasons is the ingress of coolant into the oil system due to burnout of the jumpers in the gasket between the valve head and the engine cylinder block. Liquid from the cooling system enters the engine crankcase through the burnt area. A mixture of coolant and oil is formed, the viscosity of which instantly drops, as a result of which the oil pump is unable to create the required pressure. Also due to cracks and microcracks that appear as a result of engine overheating.
Using low-quality fuel can lead to the same result. Burning not completely in the combustion chamber, it enters the crankcase through leaks in the piston rings.
There is another possibility of fuel getting into the crankcase: from the cavity of the fuel pump. The cause may be membrane failure.
The likelihood that the rubber seals will collapse and the tightness of the system will be compromised is high when replacing mineral oil with its synthetic analogue or vice versa. Different brands of oils vary in temperature resistance. For example, at low temperatures it becomes highly viscous, and at high temperatures it becomes too liquid. We should not forget about the existence of oils manufactured in violation of technical specifications. When choosing a lubricant, you need to carefully study all its characteristics.
If the oil pressure light blinks at idle, then you should check the true value of oil pressure.
After changing the oil, the oil pressure light is on: reasons
Indeed, in some cases, immediately after changing the oil, an indicator in the form of an oil can lights up. The inclusion of a red icon can mean both simple and solvable problems, and more complex ones.
In particular, if the oil pressure light comes on immediately after the car's ignition is turned on, this may indicate that insufficient oil was poured into the engine. It is worth measuring the oil level again and adding the required amount of working fluid.
It is also quite likely that the reason is the use of low-quality oil and filter. When choosing an oil filter for your car, you should pay special attention to the brand of the product. It is best to use the filters recommended by your vehicle's manufacturer. It is quite possible that when changing the oil, a low-quality or simply defective filter was installed that cannot hold oil. In this case, repeated replacement of the fluid and filter cannot be avoided.
High-quality components are ways to eliminate engine problems for a long time
A more serious problem will be a malfunction of the oil pump. As a rule, when flushing the engine before changing the oil, it experiences greater pressure, and therefore if the pump was already in poor condition, it is quite possible that after changing the oil it will fail. It is quite difficult to replace this spare part yourself - you will have to remove the engine sump, so it is advisable to contact a service station.
Main reasons
- Minimum oil level. Today this reason is considered one of the most common. When using the vehicle regularly, it is recommended to carefully monitor the oil level and try to notice various drips on the engine body. Any, even the smallest oil stains under the car are sufficient reason to check the oil system.
- Using bad filters. A certain amount of oil should always remain in the filter, regardless of the stop of the power unit. This is required so that the effect of “engine oil starvation” does not form. As practice shows, many low-quality filters do not retain oil, so it flows into the crankcase without any problems. The only way to cope with this situation is to replace the filter with a better one.
- Wiring fault. Very often the oil pressure light stays on for a long time due to wiring problems. It is located on the panel and connected to the sensor via a wire. If the oil pressure drops below a certain level, the sensor closes the light to ground. When the pressure becomes normal, the contacts open and the light goes out. However, if the sensor itself is broken, the light will not turn off. In this situation, it is necessary to conduct a thorough diagnosis, replace the wiring, as well as parts that have failed.
- Reducing valve failure. If the pressure level is minimal, then the working pressure relief valve will be located in the closed position. If it freezes or gets stuck in the open position, the required pressure will not be generated in the system, and accordingly, the light will be constantly on.
- The pump screen is clogged. It is this part that is responsible for effectively protecting the pump, as well as the power unit, from the penetration of all kinds of debris onto various surfaces. Hard chips, dirt, dust and other objects - all this has a negative impact on the surface of numerous parts. If the oil is clean, free of all kinds of contaminants, then it easily passes through the mesh. At this moment, the sensor is set to a “quiet state,” which confirms the normal functioning of the motor. However, when the oil becomes dirty and moves poorly through the filter, it is not possible to provide the required pressure. To solve this problem, it is necessary to replace the oil pan.
- Oil pump failure. If this device cannot guarantee the pressure necessary for high-quality lubrication, then the contacts are closed, accordingly, the light will constantly signal to the driver that there is a fairly serious malfunction in his vehicle.
If the pressure light is dim, you should check the wiring or replace the light bulb itself.
You can learn about the oil pressure in your car from the article What is the oil pressure.
Oil pump
With prolonged use, the gap between the gears and the pump housing increases. High production on the working surfaces of the oil pump and plus a clogged oil receiver grid can cause the oil pressure light to blink.
But don’t forget about one more point: the splined connection of the oil drive with the oil pump rod. A wear in this connection can cause the oil actuator to rotate relative to the rod under load. “Failure” of the spline connection will be the result of this rotation, and the signal will be the blinking of the oil pressure light at rpm, and often its continuous burning.
Checking the oil filter
Next we move on to checking the oil filter. It is possible for a foreign object (metal shavings, debris, etc.) to get under the shut-off valve, preventing it from closing. As a result, when the engine is stopped, the lubricant from the filter flows into the crankcase. Upon subsequent startup, the oil pressure light blinks at idle until the filter is refilled. The filter itself may also be clogged, preventing sufficient pressure from being created.
The oil pressure light appears only at high speeds, what should I do?
High engine speeds suggest vehicle movement. That is, if the oil pressure light comes on while driving, this indicates a drop in oil pressure of less than 0.5 kg/cm3. And this mark is considered critical for the power unit, since lubrication is not enough for the correct operation of the elements rubbing against each other.
High engine speed is turning over 4000 times per minute. That is, the car speed is approximately 145 km/h. At these speeds, if the driver frequently operates the vehicle in this mode, oil is used up faster - the engine needs large amounts of lubrication to operate at maximum utilization.
Accordingly, if the oil pressure lamp lights up at high speeds, then most likely the problem lies in an insufficient amount of oil itself. You will need to measure its level and add the required amount of oil to the engine.
In addition, due to a sudden transition to increased speed, the oil pump may fail. If the pump is already very worn out and requires replacement, operation at high speeds will most likely damage it. The part will need to be replaced with a new one.
What actions should be taken if the pressure sensor is on?
So, if the sensor lights up while starting the engine, but then does not go out, the first thing you need to do is turn off the engine. It is important to make sure what the oil level is in the system. This can be done using a special probe, or pay attention to the instrument readings on the dashboard.
The fact is that the oil pump takes time to disperse the lubricant throughout the system, fill the channels and pipes in order to create the necessary pressure. This causes the light to light up for 3-5 seconds. A longer period of time when the sensor burns indicates a breakdown, or that there is not enough lubrication in the system. You can try to add lubricant, but there is a danger of overflow. It is necessary to add the substance strictly according to the rules - into a cold car, out of the blue.
