We hate to say it, but engine knocks are not a good sign. There are several reasons why your vehicle’s engine is knocking, and many of them are caused by serious engine damage. Dave’s Auto Repair can find the source of your car’s engine knocks and recommend the best course of action to fix it. Here are four of the most common reasons behind engine knocks.
1. Low-Octane Gasoline
If you put the wrong gas in your car, the engine will knock. Usually, this is because the octane is too low. For example, if you drive a high-performance vehicle, it will require a higher octane than 87. If you just filled up your tank and the engine starts to knock, it could be the gasoline. Make sure to fill your car’s tank with quality gas that has the octane level recommended by the vehicle’s manufacturer.
2. Bad Engine Timing
A very basic explanation of how your vehicle’s engine works is the fuel pump pushes gas through to the fuel injectors. The injectors spray gas to mix with air in the cylinders. The spark plugs generate a spark to set the air/fuel mixture on fire, and this creates the combustion needed to start the engine. If the spark plugs are not firing correctly, your engine’s timing will be off and you’ll hear the cylinders knock.
3. Lean Fuel Mixture
If the fuel pump, lines, filter, or injectors are clogged, you will not get enough fuel in the air/fuel mixture and this will make the mixture “lean.” A failing oxygen or mass airflow sensor can also affect the air/fuel mixture, as can the carburetor. Anytime you have a lean mixture, your engine will knock and might also hesitate to start and accelerate. This is because there isn’t enough fuel in each engine cylinder.
4. “Rod Knock”
Another basic explanation is in order to explain rod knock better. When your engine is running, the pistons are moving up and down to turn the crankshaft. When the crankshaft turns, it sends power to the wheels. The rod bearings are what help the pistons to move up and down smoothly, and if they wear down, the pistons will bang against the crankshaft. This can cause serious engine damage.
Don’t take chances. Your engine could be knocking because the rod bearings have worn down and if the pistons keep knocking against the crankshaft, you could be looking at catastrophic engine damage. Call Dave’s Auto Repair in Goshen, IN, today and talk with us about your engine knocks.
