I’m Concerned That My Engine Keeps Knocking

We here at Del Hatt Automotive understand and agree with your concern over your engine knock. A knocking engine can be a sign that the cylinder block is getting damaged. Bring your vehicle to our shop right away so we can inspect the engine and determine why it keeps knocking. We are going to list the common causes of a knocking engine below for your information.

Faulty Knock Sensor

Your engine has a sensor that is installed so it can determine if the engine is knocking. This sensor will notify the engine control unit if it hears any knocks. If the sensor goes bad, it will not notify the unit that the engine is knocking and the unit will be unable to correct the problem.

Lean Fuel Mixture

One problem that the engine control unit can correct is a lean fuel mixture. This means that there is more air than gasoline in the mixture. This mixture will fire multiple times instead of just once in each cylinder. It is these multiple firings that cause the engine knocking sound.

Low-Octane Fuel

Another thing that will fire multiple times is low-octane fuel. In other words, if you drive a sports car, you can’t put fuel with an octane rating of 87 in it. If you do, the high-performance engine will knock because the fuel will fire multiple times in the cylinders.

Misfiring Spark Plugs

If the spark plugs are misfiring, they, too, can cause multiple firings in each cylinder. One reason why spark plugs misfire is that they need to be replaced because they have reached the end of their life. You may also have a problem with the engine control unit and, as such, it may be firing the spark plugs multiple times instead of just wants.

Worn Rod Bearings

If the problem is in the cylinder block, the knocking sound you hear is the pistons crashing against the cylinder walls. This is a sign that the rod bearings have worn out and the rods are no longer able to move the pistons up and down inside the cylinders without them making contact with the cylinder walls. This can damage or cylinder block.

Loose Accessory Belt

Finally, you may be hearing what sounds like the engine knocking but is actually the accessory belt slapping around because it is too loose. We can tighten it if this is the case.

Call Del Hatt Automotive in Poughkeepsie, NY, today to schedule an appointment for an engine inspection if your engine is knocking all the time. We will fix the problem.

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