A tachometer is a device used in a car to measure engine revolutions or engine crankshaft revolutions.

Thus, the tachometer pointer indicates the number of crankshaft revolutions per minute on an analog or digital display.

RPM fluctuations are not one of those things you can just wave your hand at and start dealing with only when the worst happens. There can be several different causes if your engine's speed fluctuates. Without a thorough inspection of the car and its condition, it is tough to determine the problem.

We have already covered the topic of RPM fluctuations in the past. However, this article will look at one of the specific causes of engine power fluctuations, the name of which you will surely know - a faulty lambda sensor.

RPM fluctuation is one of the most common problems among all kinds of cars, regardless of age. This topic has been widely discussed a million times on various automotive forums. However, no one wants to search through long discussions to find an answer to this problem.

That's why we decided to prepare an article with the 12 most common reasons that cause fluctuations in engine speed. To begin with, it should be noted that the RPM fluctuation does not have to be due to just one malfunction.