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Things That Make Your Car’s Engine Knock

If your car’s engine is telling you knock-knock jokes, head straight to Fast Lane Automotive so we can determine the source of the knocking noise. Ignoring the sound can actually damage your engine, especially if the knocking noise is being caused by the rods and rod bearings. Rather, you should determine the source of the knock right away and have it repaired.

Low-Octane Fuel

One thing that is easy to fix is the fuel that you place in the fuel tank. If you drive a high-performance automobile and place fuel with an octane rating of 87 in the tank, the engine is going to knock. Once you switch to the fuel with the correct octane rating, your engine will stop knocking.

Faulty Knock Sensor

Another easy fix, for us anyway, is to replace the knock sensor if it has gone bad. When this happens, the sensor no longer talks with the engine control unit to tell it that the engine is knocking. Consequently, the engine will continue to knock because the unit does not resolve the problem.

Lean Fuel Mixture

For example, if your engine is knocking because there is too much air in the combustion chamber, the unit may not add fuel if the knock sensor does not tell it that there is something wrong. Correcting a lean fuel mixture can include replacing a clogged fuel filter or cleaning the fuel injectors.

Misfiring Spark Plugs

The engine is also going to knock if the spark plugs are misfiring. In this case, if they are worn, we will replace them to prevent the knock. The problem might also be the engine control unit. It controls the firing sequence. If it is malfunctioning, we may need to replace it.

Worn Rod Bearings

We mentioned above that your engine can be damaged if the cause of the knock is the rod bearings. The pistons are moved up and down inside the cylinders by rods. The bearings help move the rods up and down. If they are worn, they may cause the pistons to knock inside the cylinder walls. The continued contact can actually damage the pistons and the cylinders.

Loose Accessory Belt

Finally, your engine may sound as if it is knocking when it actually isn’t if the accessory belt is too loose. The sound that you hear is actually the belt flapping around inside the engine. It can make contact with various engine parts.

Call Fast Lane Automotive in Orlando, FL, today if you hear knocking sounds coming from your car, truck, or utility vehicle’s engine. We will get to the bottom of the problem.

Photo by algre from Getty Images via Canva Pro