What Is Engine Knocking? | Penney Auto Body & Glass Vancouver

What Is Engine Knocking? | Penney Auto Body & Glass Vancouver

Engine knockingis a term used to describe an abnormal sound made from a vehicle engine when there’s a problem with the controlling of fuel and air mixture within the engine cylinders.

Typically, the knocking can be heard when the car is idling. It can have a strong or weak knock. A strong knock normally indicates an issue that should be fixed immediately to avoid permanent damage to the vehicle's engine.

Reasons for Engine Knocking

Engine knocking is caused by an explosion that happens outside your engine’s normal timed rotation. There are several reasons that can cause the timing to be off and cause your engine to ping or knock. These include:

  • Improperly mixed fuel
  • Irregular cylinder pressure
  • Low coolant level
  • Sharp edges on valves or pistons
  • Overheating
  • Overheating exhaust valve
  • Wrong spark plugs
  • Problems with cooling system
  • Slipping fan clutch
  • Improper Gasoline Octane

How to Fix Engine Knocking

1. Octane Rating –The octane rating of gasoline is often referred to as anti-knock index (AKI). If you use gas that has an AKI that is too low, you can use an octane enhancer to bring it back to levels that will enable normal function. If you use the correct rating and your engine still has problems, consider using a different brand of gasoline. Using gasoline with a higher AKI than the manufacturer suggests shouldn’t have any negative effect on your car's engine.

2. Use a Detergent –Your vehicle cylinder walls can attract carbon deposits. When deposits form, compression can increase and cause knocking. While most fuel consist of a small amount of detergent to avoid these build-ups, putting additional detergent to keep the engine cylinders clean does not hurt. Talk with your local auto body or dealership to see what detergent is most effective for your car's engine.

3. Check Spark Plugs –If your car does not have the right spark plugs installed, knocking can take place. Consider changing your spark plugs if changing your gas does not work. Review your owner’s manual to find out what your manufacturer suggests.

Penney Auto Body & Glass, Vancouver’s Auto Body Collision Repair Shop, is an expert in paint and body repair and cares about the welfare of your car and your personal safety. If you get involved in an automotive accident or you're a victim of a vehicle break-in or theft be sure to 
contact Penney Auto Body for your auto body, collision repair, and car painting services.


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