Generally, engine knocking noises are caused by a problem with the detonation in the cylinders. There are two other reasons why your vehicle’s engine will knock all the time. Accurate Auto Center is going to list all of the causes of engine knock below. If your engine is knocking, we can find the source of the problem and fix it.
Bad Engine Timing/Misfiring
Each cylinder in your engine has air and fuel in it that is ignited by the spark plugs. You have one spark plug per cylinder. If the spark plugs misfire, you may end up with more than one detonation in each cylinder. When this happens, the engine knocks. The spark plugs can misfire because your vehicle’s main computer chip is malfunctioning or the plugs are worn.
Faulty Knock Sensor
There is a knock sensor in your engine that is designed to notify the main computer chip if there is a detonation knock in the cylinders. This allows the main computer chip to make adjustments to the air and fuel or how it fires the spark plugs to stop the knocking. If the knock sensor goes bad, it will be unable to detect when the engine knocks. Consequently, the engine will continue to knock.
Incorrect Octane Rating
Another thing that can cause multiple detonations in the cylinders is fuel with a lower octane rating than what is recommended for your automobile. For example, you should not put fuel with an octane rating of 87 into a high-performance engine. This will cause multiple detonations in the cylinders and an engine knocking sound that you can hear clearly.
Lean Fuel Mixture
Sometimes, the air and fuel mixture in the combustion chamber has too much air in it. This is called a lean fuel mixture and it tends to make engines knock. The reason why is that there isn’t enough fuel in the mixture for the spark plugs to fire up the mixture one time only. Rather, the excess air causes multiple detonations in the cylinders.
Worn Rod Bearings
Your engine might also be knocking if there is a problem with the rod bearings and rods. This is not a detonation problem. Rather, it’s a problem in your cylinder block that can seriously damage it. The rods move the pistons up and down inside the cylinders. If the bearings are worn, the pistons will knock against the cylinder walls. This is the sound you hear.
Loose Accessory Belt
Finally, if your vehicle’s accessory belt is too loose, it may flap inside the engine and hit engine parts. This could be the knocking sound that you hear coming from your engine.
Accurate Auto Center is the best auto service shop in Tomball, TX, so give us a call today if your engine is knocking all the time.