What Are the Things That Make An Engine Knock?

The most common reason why your car, truck, or utility vehicle’s engine knocks is a detonation problem. A detonation problem means you have multiple detonations in the cylinders instead of just one in each cylinder. The multiple fireballs create the knocking sound. Techway Automotive advises that it’s important to find the source of your engine knock as soon as possible to avoid damaging the engine.

Bad Timing

One thing that can create multiple fireballs in the cylinders is bad engine timing. This can be caused by worn spark plugs or a faulty engine control module. If the engine control module is malfunctioning, it may fail to fire the spark plugs in the correct timing order. Consequently, you will end up with multiple firings and a knocking sound coming from the engine.

Lean Mixture

Another cause of detonation problems is a lean fuel mixture in the combustion chamber. What this means is that there is more air in the mix than fuel. Consequently, your engine will become fuel-starved and suffer from engine performance problems. In addition, the lack of fuel will create multiple detonations in the cylinders and an engine knocking sound.

Wrong Fuel

Another thing that can cause multiple firings in the cylinders is the wrong fuel. For example, if you drive a vehicle that requires 91 octane and you put a lower octane in the tank, your engine will knock. High-octane fuel fires quickly and singularly. If the octane rating is too low for your engine, the fuel will fire multiple times in the cylinders. Make sure to put the correct octane in your tank.

Bad Sensor

Your engine is equipped with a knock sensor that is designed to detect detonation knocking. Once it realizes that there is a problem, it alerts the engine control module so it can make adjustments to the air and fuel mixture in the combustion chamber. This system generally corrects the engine knocking by itself. If the knock sensor is bad, however, the engine control module will be unaware of any problems.

Worn Bearings

Finally, there is a cause of engine knock that is not related to detonation. If you hear knocking sounds every time you drive your automobile, it’s possible that the noise you are hearing is the pistons banging against the cylinder walls. This can happen when the rod bearings wear out and are no longer able to push the rods up and down evenly.

Techway Automotive in Blakely, GA, or Opp or Dothan, AL, can figure out why your engine is knocking. Call us today for a service appointment.