6 Reasons Why Your Engine Is Knocking

March 5, 2023

Have you ever heard a knocking sound coming from your car’s engine? If so, it could be a sign of an issue that needs to be addressed. At Rob’s Automotive, we understand the importance of maintaining your vehicle and want to share some common causes of engine knocking.

Insufficient Oil

One of the most common reasons for engine knocking is insufficient oil. When the oil level in your engine is too low, it can cause parts to rub together and create a knocking sound. To prevent this from happening, make sure you check your oil levels regularly and top off as needed.

Incorrect Fuel

Another reason for engine knocking can be due to incorrect fuel. If you are using fuel that has a low octane rating or is contaminated, it can cause the air-fuel mixture in your cylinders to detonate in more than one place at a time — resulting in a knocking sound. Be sure to use the correct type of fuel recommended by your manufacturer.

Bad Spark Plugs

Bad spark plugs can also lead to engine knocking. Over time, spark plugs will wear out and need to be replaced. If they are not replaced when needed, they can misfire. This may lead to an uneven air-fuel mixture, ultimately resulting in a knocking noise coming from the engine.

Bad Belt or Tensioners

If you hear a rattling noise coming from your engine when running, it could mean that the belt or tensioner has worn out or broken down over time. This can cause other components, such as pulleys or alternators, to come into contact with each other and create a knocking sound when running. 

It’s important to have these inspected regularly by an experienced technician at Rob’s Automotive, so any potential issues can be identified early on before they become more serious problems down the road.

Faulty Knock Sensor

A faulty knock sensor can also be the culprit for loud noises, poor performance, and decreased fuel economy. The knock sensor detects vibrations caused by detonation in the cylinders. It sends signals back to the engine control unit (ECU), which adjusts timing accordingly in order to prevent further damage from occurring due to detonation. 

If this sensor fails or becomes damaged over time, it won’t be able to detect vibrations. As a result, you’ll end up with additional issues with your vehicle’s performance and potential damage if left unchecked for too long.

Damaged Crankshaft

The crankshaft is responsible for converting rotational energy into linear motion, which helps power your car’s wheels forward when driving down the road. If this part becomes damaged due to wear and tear, it can lead to an imbalance within the cylinders. You’ll probably hear a loud knocking noise coming from under the hood when driving at higher speeds or accelerating quickly after starting up from idle speed. 

It’s important that any issues with this part are addressed immediately by an experienced technician at Rob’s Automotive before further damage occurs.

Rob’s Automotive: The Area’s Leading Service and Collision Center

At Rob’s Automotive, we understand how important it is for our customers’ vehicles to run smoothly all year long without any unexpected surprises along the way. We’re certified by 24 major auto manufacturers and have the experience to provide repairs on any type of vehicle. 

From heavy-duty truck repairs to towing services throughout the Philadelphia area, Rob’s Automotive has you covered! If you ever find yourself needing help with anything related to automotive service and repair work, don’t hesitate to reach out to us. We look forward to hearing from you soon!