The oil light is flashing. Causes and solutions

The engine is the most important component of a car. It has many parts that ensure its proper functioning. When all these parts work, in a high-temperature environment and loads, constant, abundant lubrication is required. All engine parts are supplied with lubricant thanks to an oil pump.

When the Electronic Control Unit detects a problem with the oil it will store the error and, in most cases, the oil light error indicator will show up in the car’s dashboard either lighting up constantly or flashing.

There are many causes why the oil light is flashing, the most common ones are:

  • Using a low-quality or an incorrect engine oil;
  • Loss of oil through gaskets and oil seals;
  • Low oil pressure in the engine;
  • Problems related to the oil pressure sensor and its wiring;
  • Bad or clogged oil filter;
  • Bad oil pump.
  • A bad pressure reducing valve

Newer car models have separate oil light error colors, while others, usually older car models, have only one oil light color. The oil light is activated when the oil pressure in the engine crankcase is low. Usually, yellow oil light on the dashboard means a low oil level, and a red indicator means that the oil has low pressure.

yellow oil light error

The oil light errors can be activated separately from one another since they work according to data from two sensors, level sensor, and engine oil pressure sensor. For example, even when the oil level is low, the oil pump is able to provide sufficient pressure. Although it depends directly on the level, if the level is very low, then there will be no pressure, but if the level has dropped slightly below the minimum mark, then the pressure will still be there.

 And if the oil level is within the normal range, for example, with a clogged oil filter, then the pressure in the system is insufficient for effective lubrication of engine parts. 

A good example here is the situation when the crankcase breaks, triggering first the low-pressure oil light, and then the low oil level indicator.

Now let’s talk more about the common causes that trigger the oil light error on the dashboard. Some of the reasons cause the oil light to remain constantly on and rarely make it flash. But we will focus more on the ones that trigger a flashing oil light.

Using a low-quality or incorrect engine oil

This is one of the most common reasons that make the oil light error blink. The use of an incorrect viscosity of the oil is caused by the lack of interest of the car user. He doesn’t know, but he also doesn’t look in the car’s manual to check the correct oil options he can use.

Using a poor-quality or a clogged oil filter

The role of the oil filter is to ensure that foreign material, dust, and other debris won’t enter the engine keeping the oil clean. Moreover, the oil filter will keep a small amount of oil in it when the engine is off and avoid oil starvation when the engine is turned on after a while.

If the oil filter is bad or it is of low quality, then, after the engine is turned off, the oil in it can be drained in the oil pan, and after starting the engine, for a few seconds the friction will be done with no oil and this could mean accelerated wear for the internal parts of the engine.

In this case, the low oil light error will turn on and possibly flash, but after a few seconds will turn off.

A clogged oil filter, on the other hand, will trigger the “check oil pressure” light most of the time and it can have strange behavior like it might stay on all the time, blink or turn on and off.

A clogged oil filter will not allow the flow of engine oil to pass through as it should. This leads, firstly, to a decrease in oil pressure in the system, and secondly, it creates an additional load on the oil pump, which reduces its resource.

A failing or dirty oil pump

After a certain period of time, the water pump can fail and needs to be replaced. If these oil pumps are not working, the pressure in the system will not be maintained, which means that the oil light will also flash.

Also, another cause is represented by a clogged mesh of the oil pump, similar to what happens with a clogged oil filter, less oil passes through the mesh than it should, which leads to a decrease in oil pressure in the system and a decrease in its level. Moreover, this will have a negative impact on the oil pump because it will accelerate its wear.

Oil leaks

Oil can leak through worn-out seals, gaskets o-rings, but also on broken pipes or oil channels. If the oil leak is significant, this will reduce the pressure in it which will cause a flashing oil light (pressure error) or to be constantly on.

Bad oil pressure sensor and its wiring

Another reason may be the incorrect operation of the oil sensors, especially the low-pressure sensor. This sensor can fail and will need to be replaced. On the other hand, pay close attention to the sensor’s wiring, there might some messed-up wires there as well.

A bad pressure reducing valve

A pressure-reducing valve in the oil pump is responsible for maintaining the oil pressure at the proper level, if it fails, the oil will be unevenly distributed between the parts of the internal combustion engine, which leads to an oil level drop. This will trigger a flashing oil light.

Possible solutions of a flashing oil light

A blinking oil light error indicator may appear on the car’s dashboard either when the engine is idling or when you drive. If this happens, a simple solution is to turn off the engine, let the engine cool for 10 minutes if outside temperatures are low or 25-30 minutes on summer time. This will cool the engine and will let you accurately know how much oil there is in the engine.

If you see on the dipstick a low oil level, you can try to add more oil to see if the problem fixes. Add the same oil that is in the engine. Try to not mix oil viscosities, because it is not recommended. But on this critical situation you can mix engine oils until you get on the nearest repair shop, flush the engine entirely, add fresh oil and also change the oil filter.

If this doesn’t fix the problem, try not to drive with a flashing oil light. This can do other damage to the engine that can be expensive to repair. Instead try to tow the car to the repair shop to perform a thorough check.

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