Bad Piston Rings Sound and Other Signs They Are Worn

Bad piston rings don't make almost any sounds, but when they are worn out, you can spot abnormal oil consumption and buildup formation on injectors and spark plugs. The reason for this is the fact that worn-out rings let oil come to the combustion chamber and burn there forming a lot of buildup, black or grey smoke, etc.

Engine leaks highlights

• Level of importance:Medium
• Commonreasons:Problems with seals and gaskets, internal failures
• DIY inspection:Possible but complicated
• DIY repair:Mostly,impossible
• Price for repair:$150 - $650
• Can you drive?Only if the leak is minor
• Ways to fix:Replace the broken gasket or seal, replace the failed part

Here's what I will cover in this article:

• Can you potentially locate bad piston rings just by listening to the weird sounds?
• What are the symptoms of worn piston rings?
• What will happen if you ignore bad piston rings?
• How much does it cost to replace the piston rings?
• How long can you drive with worn-out piston rings?

Let's get started!

Piston rings and bad sounds - any connection?

Actually, bad piston rings will probably make some sounds deep inside the engine. But you will not hear it however carefully you listen to it. You need to understand what happens with worn-out rings.

When piston rings are in good condition, they form a type of skirt around the piston. There are two types of these "skirts": the one for sealing oil in the crankcase and the one for sealing compression in the combustion chamber. But when they go bad, they basically become level with the piston and don't touch the cylinder wall. Of course, they only make less sounds this way.

If a piston ring is damaged or broken, it may also scratch the cylinder wall. In this case, it will make some kinds of sounds but the problem is that these sounds are not really loud and you can't hear them outside the engine.

Also, other engine sounds will obviously take over bad piston ring sound and will not allow you to hear the engine asking for help. It's a great problem for car owners because bad piston rings are very hard to locate and diagnose but they can easily kill the engine if they are completely worn and damaged.

So, you shouldn't rely on some scratching sounds when you are trying to diagnose bad piston rings in your vehicle. It's only possible to locate this problem when you pay attention to other symptoms and signs.

Important symptoms of dying piston rings in your engine

Unfortunately, you don't have the opportunity to easily locate bad pistons. Also, each of the symptoms that I'm posting below can be related to other problems. So, you will still need to take the engine apart to make sure that the problem comes from the piston rings.

Here are the symptoms of bad piston rings:

1. Growing oil consumption

The primary task of the piston rings is to not allow the oil that lubricates the cylinder to enter the combustion chamber. Once the ring is faulty, some oil will get into the chamber and start burning.

2. Grey smoke from the exhaust pipe

This symptom comes from the previous one. When oil is burning in your engine, grey smoke is formed and it's emitted through the pipe.

3. Low oil levels

This one is also connected with the first symptom. If the oil burns, the level of it will obviously drop. This can lead to other problems if not spotted at the right time.

4. Poor engine performance

If compression rings are bad, your engine may lack compression in certain cylinders. It may misfire, lose power, or one cylinder may just stop working. But keep in mind that there are other possible reasons for compression drop.

5. Carbon buildup on spark plugs

Your spark plugs are located in the combustion chambers and if some oil comes there, they burn it. As a result, they are often covered in black buildup that is the product of oil combustion.

6. Contaminated catalytic converter

If this problem is not addressed on time, it can affect the catalytic converter. When a lot of oil is burnt in the engine, the converter may get clogged and eventually stop working. This will affect the engine work and cause the check engine light.

7. Check engine light

Although the ECU doesn't check the condition of piston rings, bad rings can easily trigger the check engine light. This happens because of engine misfire, lost performance, catalytic converter problems, or other consequences of bad piston rings.

8. Destroyed cylinder walls

If the problem is not addressed once it starts developing, you can end up having a destroyed engine. Bad piston rings may scratch the cylinder walls which will lead to really bad damage to the block.

Why ignoring bad piston rings is not an option?

Usually, piston rings live as long as the engine. Their average lifespan is considered to be about 180,000 miles in modern engines. But sometimes, the engine may still last longer and it's worth repairing it.

Ignoring bad piston rings, in this case, will lead to the sooner engine death. Just look at the common signs of the broken piston rings that I listed above and count how many of them can potentially kill the engine or take its performance to almost zero.

If you ignore this problem, the engine may seize within several months. But sometimes, small issues with piston rings can be there with your engine for years and they don't affect the overall performance of the powerplant.

How much is it to replace the piston rings?

Installing new piston rings may sound like a good solution to your problem. You get rings that don't cost a lot and try to find the simple step-by-step instruction on how to do it. But every article or video tutorial you open on the internet is so complicated that you don't understand how to do it. Why?

Because it's an extremely hard job and you won't be able to accomplish it if you don't have good experience as a car mechanic.

Here's how it happens:

• you need to take the head off the engine to get to the pistons;
• then, your task is to take apart the bottom part of the engine;
• you are left with the block and now you can take off the pistons;
• take off the old rings and install the new ones;
• insert each piston and fasten it as needed;
• assemble the entire engine lubricating all its inner parts;
• turn the engine with a tool without starting it to check if everything is fine;
• try starting the engine (don't forget to fill it with oil and coolant before).

It may sound easy but even when you are on the first step, you may understand that this task is not for you.

So, the price of replacing piston rings is ridiculously high just because the mechanic will need to take apart the entire engine and then assemble it back. There is no other way you can get those pistons out of the cylinder block.

The average labor price should be about $1000 in an independent shop and $3000 and more in a dealership. Sometimes, it's better to buy a new engine and have it installed. This will be more or less the same price in the end.

Can you just keep driving with bad pistons?

When you go to a repair shop and ask them how much it costs to replace the piston rings, you may conclude that driving with worn-out rings is not a bad option. But this is kind of a lottery that you are going to lose in the end. You never know when fatal oil consumption starts and when your engine is no longer able to drive.

Driving with a bad piston ring is possible but you should understand that oil consumption leads to engine contamination, oil level drop, catalytic converter damage, and other effects. It means that after some time, all units of your vehicle will require repair or replacement.

If you aren't ready to pay for the new engine or for the piston ring replacement, your option is to sell the car and buy the new one. Sometimes, it's cheaper and more convenient than trying to solve the piston-rings problem with your vehicle.

Final thoughts

I believe that the piston-ring problem is one of the most common reasons for engine failure. In the US or in the majority of European countries, it's not actually reasonable to replace the piston rings because the labor is extremely expensive. Sometimes, replacing the engine is a more lucrative solution.

Although the problem with piston rings sounds like a minor issue and the set of rings may cost you something about $50, you should remember about the labor prices. Maybe, you will find a mechanic who will agree to do this job for less money. But the quality of the work is also extremely important.