If your car’s engine sounds like a diesel truck, you are likely hearing knocking sounds. Our team advises that a knocking engine is an indication of either a detonation problem or an issue in the cylinder block. It’s important to have the knock looked into as soon as possible to avoid engine damage. Let’s talk about the reasons why an automobile’s engine will knock constantly below.
87-Octane Fuel
If you drive a high-performance vehicle, putting 87-octane fuel in the tank is going to make the engine knock. You should only have one firing in each cylinder per spark plugs spark. Low octane fuel tends to fire slowly in a high-performance engine and this will cause it to detonate several times instead of just wants. The knocking sound that you hear is the multiple detonations.
Bad Engine Timing
As we just mentioned, there should be one detonation per spark plug spark. If the spark plugs are not firing in the correct order, this bad engine timing will cause the engine to misfire and knock. This problem can be caused by worn spark plugs or an engine control unit that is going bad.
Bad Knock Sensor
Your engine may also knock and sound like a diesel truck if the knock sensor is malfunctioning. When this happens, the sensor fails to communicate with the engine control unit to let it know that the engine is knocking. Consequently, the engine control unit cannot fix the problem that is causing the knock.
Lean Fuel Mixture
You may already know this but one problem that will make your car’s engine knock is a lean fuel mixture in the combustion chamber. This mixture will detonate multiple times instead of just once. Naturally, these multiple detonations make that rattling diesel engine sound.
Worn Rod Bearings
If the bearings that move the rods up and down have worn out, you may end up with a knocking engine in the cylinder block. Bad rod bearings cannot move the rods up and down without causing the pistons to bang against the cylinder walls. That contact is the knocking sound you hear.
Loose Accessory Belt
Finally, your engine may not be knocking at all. Rather, you may have a loose accessory belt that is flapping. This sound can mimic the sound of engine knock. We can tighten the accessory belt to prevent it from moving around and making this noise.
We can also correct the problem that is causing your engine to knock. Call us today for an appointment.
