Engine Noise

Engine Noise: What Is That “Knocking” Sound?

Whenever you start your engine, and when ever you turn it off, it should be smooth. Every so often there may arise an engine noise that can otherwise be questionable. Some of these sounds can be alarming while others can just be mildly annoying. Whatever the case may be noises coming from underneath the hood are never something that you want to ignore for long. These noises can lead to costly repairs.

What does a “Knocking” Engine Noise mean?

One of the most concerning sounds can be a “knocking” sound. This is the most common engine noise that we see. You should not ignore this engine noise. This problem can be for a variety of reasons and this engine noise is quite easily fixed.

Knocking noises in your engine can best be described as a small pinging sound. This engine noise can mean one of several PROBLEMS. The most likely reason for this noise is that the air fuel mixture is incorrect. This causes fuel to be burned in pockets of air that are uneven. This can and will eventually cause damage to the walls of the piston cylinders. Another culprit for this noise can be a lack of lubrication in the cylinder head. The ticking of pinging sound can be is created when the valves and cylinder lifters are not receiving enough lubrication or oil.




Your Fuel may have a low octane rating or level

When you fill your vehicle with fuel and you are using a low octane rating, especially a rating that is too low for your vehicle, it can create a knock sound. Octane ratings are used to measure the fuels ability to resist detonation too early within the engine. Hence the name “combustible engine”. When the fuel explodes too early you will hear the knocking sound

To avoid this problem you will want to purchase a fuel with a higher octane rating. These are the premium and the plus fuels at the pump. Yes, the more expensive ones. You can also purchase octane boosters at your local auto part store as well. This can help to reset the octane rating in your vehicle and remove this unwanted engine noise.

There are Carbon Deposits in the Engine

The fuel that you put into your vehicle are required to have a detergent that prevents carbon build-up. That being said you can still develop carbon deposits in your vehicle. Especially if you are using cheaper gas, from cheaper gas stations. Now, you see why Chevron gas costs more. Fuel, when it mixes with oxygen is burned. Since fuels are made up of multiple carbon chemicals, residual carbon will form of the valves, plugs, and other components within the system. When all of this “gunk” builds up it does not allow for a lot of room within the system. This will increase the amount of compression within the system, causing the unwanted engine noise.

You can fix this problem by adding a fuel injector cleaner the next time that you fill up. Make sure that the cleaner is designed to remove carbon deposits. This should resolve the issue


In most cases, using a special fuel injector cleaner or additive designed to clean carbon deposits on engine components can resolve this issue.If the problem continues after you have tried to remedy these issues, please bring your vehicle in for service. There may be some deeper issues related to spark plug or wiring problems.

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