How to Extend Life of an Engine with Rod Knock

The engine of your vehicle, just like any other part, cannot stay in perfect condition always; over time, it starts to develop issues. Having a faulty engine is something that no car owner wants to go through.

One of those problems is an engine with rod knock. Engine knock could sometimes be severe and other times just light.

When you experience rod knock, it does not mean that you change your engine immediately, no! Other more straightforward solutions can help you extend the engine life and save the extra replacement costs.

Are you wondering how to extend the life of an engine with rod knock?

This article will give you suitable recommendations on how to extend life of an engine with rod knock without necessarily replacing it.

What Is Rod Knock?

Rod knock is a form of deep rapping sound coming from the engine. So if you hear a knocking sound from within the engine when you are driving, then your car has a rod knock.

Rod knock results from wearing out of rod bearings or damage.

The car’s connecting rod bearings have excess clearance that causes additional movement. When the pistons change their direction, the metals hit against each other, resulting in the knocking sound.

Rod knocks start like a slight knocking sound; it increases with the increase in your vehicle’s speed.

When you accelerate your car, the knocking sound also fluctuates and gets louder and faster; alternatively, the sound becomes quieter and slower when you slow your vehicle down.

Rod Knock Causes

The primary cause for rod knock is worn out bearings, but other reasons can show symptoms similar to rod knock.

Here are the causes of rod knock;

Worn Bearings

The primary cause of rod knock is worn bearings. When pistons move up and down in, they spin the crankshaft, which helps to send power to the wheels.

The work of bearings is to ensure that the movement of the piston is under control and smooth.

Over time, the bearings wear out; this can make them come out of their position. The wearing out of the bearings leads to the piston rods rattling against the crankshaft, creating an unusual sound.

If worn bearings cause the rod to knock, the only solution is to replace the bearings located deep inside the engine.

Lean Air to Fuel mixture

The issue results from failing fuel injectors, faulty oxygen sensors, poor mass airflow, and a faulty fuel pump.

This lean air to fuel mixture happens when there is no adequate fuel and too much air.

If the fuel amount is not correct, the combination will not be able to burn efficiently and fast enough, and this leads to detonation.

Low Octane

The air and fuel mixture burns in one detonation inside every cylinder when the engine runs. However, the detonation knock might occur when the air and fuel mixture detonates more than a single time hence causing the knocking noise.

When the engine has high octane, it will burn uniformly and prevent knocking.

To fix this problem, use a high octane fuel to fill your car the next time.

Bad Belt Tensioners

When the accessory belt lacks the correct tension amount, it makes some noise as the engine knock.

When the engine spins, the belt turns as well; if the belt becomes loose, it is an indication that the tensioner is not functioning correctly.

You can also experience issues when one pulley becomes bent. This problem causes rattles, slapping, and click noise that you can mistake for an engine knock.

It would be best to replace the pulley, tensioner, or belt to fix the issue.

Poor Timing

Bad engine timing can also cause detonation. The computer helps to control timing at the point of firing the spark plugs.

Therefore, when the timing is poor, the spark will not fire as it should be, and it leads to many detonations inside the cylinders, causing the engine to knock.

To solve this problem, fix the timing of your engine.

Bad Knock Sensor

When the knock sensor malfunctions, it causes a detonation knock.

Fortunately, it is not common in new cars because the computer controls the timing, fuel injector, and air to fuel ratio.

The knock sensor helps detect any problem that may lead to noise and send information to ECU, where correlative action happens immediately.

Therefore, if the vehicle has a faulty knock sensor, the computer cannot correct the problems, and the engine is likely to start knocking.

How to Extend Life of an Engine with Rod Knock

When you have an engine rod knock, you don’t have to keep replacing the engine your priority; some simple solutions can assist you to extend the engine life and save you the costs of replacement costs.

Here are some simple means of solving the problem and extending engine life;

1.Replace the Bearings

Bearings help to ensure rhythmic movement of the pistons and crankshaft. If the bearings are damaged, they will likely make noise.

It is best to check the bearings when you experience rod knock and ensure you replace them when necessary.

2.Replace Connector Rods

Damaged rods are a primary cause of your engine knocking.

If you notice that your connector rods are damaged, it will help replace the faulty parts, and you will have solved the engine knocking.

It is less expensive to replace connector rods compared to replacing the engine.

3.Check the Coolant Level

Coolants are air conditioner-related components that help prevent the engine from overheating.

If your engine overheats, it causes engine knocking. So, it is always good to check the coolants to ensure the engine is excellent.

4.Use Better Quality Lubricants

Lubricants of good quality allow the pistons to be able to move smoothly. Good oil or lubricators are crucial because they may result in rod knock when the pistons are dehydrated.

5.Replace Bad Spark Plugs

The connector rods and pistons are connected to the spark plugs and ignition chamber.

So, if your spark plugs are faulty, they might damage the connector rods hence making the engine knock.

If you note this problem, take your vehicle to the service center to help you replace the faulty components.

6. Don’t Overload

Every vehicle has a particular load limit. Therefore, if you overload your car, the engine will not be able to carry the loads comfortably and will likely damage some components. It might also result in engine knocking.

To solve this issue, avoid overloading your vehicle regularly.

7. Replace the Piston Rod

When you hear the knocking, it would be best to check the pistons because the noise could result from some part of the piston or the whole piston.

The pistons move up and down to spin the crankshaft and provide adequate power to move via the thin bearing rings smoothly.

If the rods change direction, the pistons are likely to hit the metal, causing the knocking sound called rod knock.

Frequently Asked Questions (FAQ)

How long will an engine last with rod knock?

There is no specific time the engine will last when it starts knocking because the rod can get damaged without any notice.

So, it could last for a brief period, like when you get your car on the road for a drive, or it can go for even six months.

It is important to note that however long it takes, it will eventually blow, and it can leave you stranded in the middle of nowhere.

Will thicker oil help the rod knock?


Thicker oil is only a temporary solution, so it will not stop the engine knocking entirely, but it can relieve the symptoms.

To alleviate the rod knock completely, you will need a proper tune.

Does rod knock mean a new engine?

When you experience rod knock, the engine is not functioning correctly.

While it does not necessarily mean that you should get a new engine, you should take immediate action, and if the bearings have a problem, replace them and fix any other component that could be causing the issue.

Does rod knock get louder with RPM?

Rod knock will get louder with increasing RPM; however, the noise is more like tapping on slamming into an object.

Can you hear Rod knock at idle?

Yes, you can sometimes experience rod knock when the car is idling. It is usually in frightening engine noise inform of loud banging sounds.

Can a rod knock go away?

Rod knock can’t go away without fixing. If you are experiencing engine knocks, ensure you check where the noise is coming from and fix it or get a mechanic to help you.

How much does it cost to repair rod knock?

It will cost you about $2,000 to $3,000 to repair rod knock both labor and parts. The work involves connecting rod bearings, replacing gaskets, seals, connecting cylinder head bolts, and flushing out cooler lines and engines.

On How to Extend Life of an Engine with Rod Knock

If you experience an engine knock, the first thing that comes to mind is the engine is broken and you need to replace it. However, it is possible to use the engine even longer by just fixing it without having to replace it.

So, how do you extend the life of an engine with rod knock?

As discussed in this article, you can replace the bearings, piston rods, and faulty spark plugs, avoid overloading, check coolant levels and ensure you use suitable quality lubricants.

However, ensure you attend to the problem of rod knock immediately it starts because you don’t know how long you will drive before the engine stops completely. It can be inconvenient and leave you stranded in the middle of nowhere.



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