I Don’t Understand Why My Car’s Engine Keeps Knocking

If your car’s engine keeps knocking no matter what you do, bring the vehicle to Mechanic One Auto Repair right away so we can determine the cause of the knocking. It is possible that continuing to drive your automobile could damage the engine severely, so it’s better that we take a look at the engine sooner rather than later. The following are causes of a knocking engine.

Low-Octane Gasoline

One thing that can make your engine knock constantly is low-octane gasoline. If you drive a vehicle with a standard engine, this gasoline is just fine. If you drive a high-performance automobile, however, low-octane gasoline will not fire quickly enough in the combustion chamber and cause engine knock. The source of the knocking sound is multiple fireballs colliding against each other.

Malfunctioning Sensor

Usually, the knock sensor will detect this problem and alert the engine control unit that there needs to be an adjustment in the combustion chamber. Unfortunately, if the knock sensor is malfunctioning, there may be zero communication between the two computer chips. This will leave the problem in the combustion chamber unchecked, and the engine will keep knocking.

Air-Heavy Fuel Mixture

One thing that the engine control unit can resolve is an air-heavy fuel mixture. When a fuel mixture has too much air and not enough fuel in it, it will fire multiple times in the cylinders. This creates the colliding fireballs we talked about above. Things that can cause this type of fuel mixture include clogged fuel injectors, a clogged fuel filter, and a faulty fuel pump.

Spark Plug Problems

Your engine may also knock constantly if the spark plugs are having problems. The problem could be that the spark plugs themselves are worn and need to be replaced or that the engine control unit is not firing them in the correct order.

Worn Rod Bearings

A source of knocking that can damage your engine is worn rod bearings. When the rod bearings where out, they are no longer able to move the rods and pistons evenly up and down inside the cylinder walls. Consequently, the pistons may contact with the walls and damage them.

Loose Accessory Belt

Finally, if the accessory built in your engine has loosened, it will whack nearby parts and make it sound as if your engine is knocking. We can tighten the belt to stop the noise.

Mechanic One Auto Repair in Canton, MI, is here to help, so call us today so we can inspect your engine to determine why it keeps knocking.

Photo by AzmanL from getty images via Canva Pro

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