Updated at: 17-08-2022 - By: Lucas

One of the most frustrating aspects of owning a car is having to deal with engine repairs. The more time you allow for faults in your engine to fester, the more difficult and expensive it is to fix. Engine problems such as rod knock are among them. Understanding engine problems is the best way to avoid them in the future. So, let’s look at the signs, causes, and remedies of rod knock.

What Is Rod Knock?

How To Fix Rod Knock

For starters, you need to know what a rod is before discussing its symptoms and causes. Why are connecting rods necessary?

The piston and crankshaft are joined by the connecting rod in a piston engine. The crank and connecting rod work together to translate the movement of the piston into movement of the crankshaft.

In order to transmit the piston’s compressive and tensile forces, the connecting rod is required. Internal combustion engines commonly use this arrangement, which allows the piston and shaft ends to rotate.

The mechanical linkage employed by the watermill to transform the waterwheel’s rotating motion into reciprocating motion is the forerunner of the connecting rod. Combustion engines and steam engines require connecting rods in large numbers.

What Does Rod Knock Mean?

One or more of your crankshaft’s connecting rods, loosening and knocking on another surface, is referred to as “rod knock.” As a result, it makes a banging or pinging sound when it changes direction or rotates.

Crankshaft and connecting rod are linked by a bearing with an extremely small gap of about 0.0001 inches. This is the rod that we keep referring to.

It is possible to keep the bearing lubricated with a thin layer of oil, but as the bearing wears, the gap widens, making it impossible for the oil to flow around it.

Though it may take several hundred thousand miles for a bearing to degrade naturally, this is more often caused by oil quality issues. Bearings might wear prematurely due to dirty oil, low oil pressure, or an insufficient amount of oil in your engine.

Symptoms Of Rod Knock

Rod knocking has a symptom that you may be familiar with. The rod’s knocking noise is the predominant symptom and the most easily recognizable sign, even if you experience other symptoms.

Your engine will make a sequence of clanking and banging sounds if you have a rod knock. When the engine revs and you let off the gas, you should hear this sound more clearly.

This is due to the fact that your engine will not be consuming gas at this time. As a result of rod knock, the engine’s noise is muffled, allowing you to hear the sound clearly.

You’ll usually hear this noise right after you take off the gas, and if you hear it, you’ve got some serious trouble on your hands.

Diagnosing And Fixing Rod Knock

How To Fix Rod Knock-2

No, it’s not necessarily rod knock if you hear banging in the engine. The symptoms of a number of other automotive problems are similar. You should have your car towed to an experienced mechanic who can correctly identify the rod knock if you hear it.

However, if you’ve worked on cars before and don’t mind getting your hands dirty, you may check to see if you’re experiencing rod knock or another issue.

The trouble with hearing a knock in the engine compartment is that it isn’t always an indication that the noise is originating from within the engine. When a complete engine rebuild is performed, many consumers are disappointed when they discover that the knocking is still there.

We should begin by checking a few things that don’t require much disassembly. Check the belt, tensioner, and water pump first if you don’t remember when they were replaced. When purchasing a car, it’s a good idea to replace all of these damaged parts, but many people do not do so in order to save money.

Crankshaft, flywheel, and valve bearing inspections should be performed if replacing suspect parts does not resolve the issue. This will take some extra time to complete, but it is necessary in order to eliminate the rod knock. Expert advice is always preferable to trying to figure out what to do on your own.

Checking The Oil Quality

Bad engine oil is a common cause of knocking noises coming from the engine.

If none of the aforementioned suggestions worked to stop the banging, and you’re positive your automobile has rod knock, the methods listed below will show you what to do and watch out for.

If you suspect that the problem is more serious, you should first change the oil and evaluate the oil quality. The banging sound may be produced by dirty oil or a change in the viscosity of the oil.

To begin, make sure the oil is in good condition and that the amount is adequate. The engine oil dipstick must be removed, cleaned with a rag, and the color of the oil checked. It’s dirty engine oil if it’s muddy or brown in hue.

If your engine oil isn’t up to par, you’ll need to reinstall it and check the quality of your oil. What you need to do is as follows:

Changing the oil should eliminate any rod knock that was caused by unclean or inadequately thickening oil. If it doesn’t stop, you should take it to a repair shop to have it fixed.

Keep an oil catch pan available as you begin this process to avoid spilling oil all over your workspace. In the end, this could lead to an unpleasant situation. Before emptying the oil, check the engine cover to see how thick the oil is utilized by the engine.

This is critical to ensure that the old oil is not replaced with the wrong type of oil. Pour the old oil into a transparent container first so you can examine it up close before you remove the cap and discard it. Immediately after removing the sample, drain the remaining oil for further inspection.

Diagnosing The Condition Of The Oil

Wear on engine parts is indicated if metal shavings can be found in the oil. Knocking can be caused by chips in the engine’s connecting rods, crank bearings, or other mechanical components.

One of the issues is that it’s impossible to tell where the metal shavings or chips came from. As a result, the oil in the engine won’t tell all.

Bearings’ brass covering will corrode over time if oil is not replaced regularly. In particular, bearings that are distant from the oil pump have a lower flow of oil than bearings closer to the pump.

You should also look at the oil’s color to see whether it has changed. If the oil is dark brown, it’s unclean or old and should be replaced. If the oil is too thin, a replacement is required immediately.

How to increase the life of your vehicle’s connecting rod and bushings is a simple matter. Engine oil should be changed according to the manufacturer’s recommendations.

Fixing Rod Knock

How To Fix Rod Knock-3

You can try the following to fix or lessen the amount of work required to remedy rod knock on your own.

This is a symptom that the engine’s internal components are malfunctioning. Rod knock can be caused by a variety of circumstances, as previously discussed. Identifying the root cause of rod knock symptoms may necessitate a number of fixes, some of which are costly and others which are not.

Things You Can Do To Solve Rod Knock

This does not imply that your computer is beyond repair, though. It is possible to stabilize the machine before contacting your dealer or mechanic by taking efforts to eliminate rod knock and perhaps.

Changing the oil on your car should be your first line of defense. With the help of your own two hands. Changing engine oil isn’t that difficult. If you are experiencing rod knock symptoms, this may be a simple and inexpensive cure.

Oil filters are next. Remove the oil filter by rotating it counterclockwise with the oil filter wrench. Install a new filter and check the recommended parameters. Change the engine oil to the same viscosity or the recommended oil that was previously used.

Both over-oiling and under-oiling can have detrimental effects on the performance of a vehicle.

There are a couple of other minor issues. To see if you can simply correct them, follow the methods below.

A knocking noise can be heard if the connecting rod cap is not properly fastened. Remove the boom and check for loose screws keeping it in place on the lid. The connecting bar bearings should be checked and, if necessary, replaced.

When refueling at a gas station, the filler hole might become clogged with dirt and other material. You’ve probably heard of the term “rod knock” before, but you may not have known that it can be caused by a buildup of dust and other debris in the oil.

These impurities can induce rod knock if they are not removed from the fuel injection system. In older cars with carburetors, you should avoid using refueling detergent because it can damage the carburetor. Instead, spray your carburetor with a vaporizer cleaner.

Before taking your car to a repair, you should perform these easy activities. A chance exists that this could succeed. However, if it doesn’t, you’re better off taking it to a mechanic.


Many people have questions about rod knock symptoms, so here are some answers.

The causes and solutions.

How Much Does It Cost To Repair Rod Knock?

Repair costs for engines with blown connecting rods are dependent on the kind, manufacture, and model of the engine in question.. Also, the engine must be removed and disassembled. Pistons, bearings, and potentially even the crankshaft may need to be changed along with the gaskets and cylinder head bolts.

This is a problem that not every service expert is equipped to handle well. Be sure to check with a few people for recommendations and estimations before making a final selection.

When faced with the prospect of spending money on engine repairs, many individuals consider simply purchasing a new vehicle. Some motorists choose for brand-new or remanufactured motors. A stem repair might cost anywhere from $2,500 to $10,000 depending on the complexity and difficulty of the damage.

Can You Drive A Vehicle With Rod Knock?

Yes, it is correct. Rod knock can be used to operate a vehicle. However, you should avoid doing this. Continuing to drive a vehicle with a knocking rod can cause even more significant engine damage and raise repair costs.

The engine’s connecting rods can break if the bearings get too hot and don’t get enough lubrication.

Your engine could be destroyed, possibly even resulting in a hole in the block. In order to avoid further damage, it’s best to have your car checked out by a trained mechanic as soon as you notice a rod bang.

How Long Do Connection Rods Last?

Depending on how well you take care of your vehicle, this question can be answered. Your connecting rod will never fail if you perform all of your regular oil changes correctly.

However, if you use the improper sort of engine oil or fail to do regular oil changes, your rod will quickly fail.


Nobody disputes that rod knock is the most serious automobile problem. However, it is frequently portrayed as an insurmountable obstacle. Because of this, when people hear knocking noises coming from their cars, they automatically assume that their vehicle is likely to die as well.

A rod knock problem is a rare occurrence in reality. However, engine noises like a squealing sound are rather typical. This means that the symptoms of rod knock are not limited to the presence of a defective rod. Alternatively, it could be a simple issue like low engine oil.

So you’ll need to learn how to identify the issue. Take a look at some of the simple fixes we’ve already mentioned. It may be able to address the problem. A mechanic will be needed if you can’t determine the source of the knocking sound.