Internal Engine Problems – Common Reasons and Solutions

Unfortunately, all engines develop internal problems sooner or later. This means that they are not eternal and will fail one day. But if you know about the common problems with modern engines, you get the chance to prevent the issues just by maintaining and servicing the vehicle as it really needs to be serviced.

In this article, I want to tell you about all the internal engine problems that I've reviewed in this blog. I will give you ideas on what to check and how to fix them. Also, I will give you links to the articles that will help you investigate the problem even deeper and find possible solutions. Hope this helps you fix the vehicle without spending too much on it.

Engine bearing problems

Your engine has a lot of different bearings and all of them have certain symptoms that can help you understand which one is failing. Cam bearings and also crankshaft bearings consist of two parts and have no moving objects in their construction. They are basically just metal plates that separate the shaft from its bed.

Rod bearings hold the crankshaft. If they fail, the crank may be damaged. When this happens, even one scratch can lead to engine locking because in your engine everything has to be perfect.

You may want to know what leads to rod-bearing issues. The reasons are almost always poor lubrication or overheating. But sometimes, the bearing may fail because of its age, overall engine wear, or physical damage.

Engine bearing problems highlights:

• Level of importance:High
• Commonreasons:Overheating, low oil pressure
• DIY inspection:Almost impossible
• DIY repair:Impossible
• Price for repair:$1,000 - $3,500
• Can you drive?Usually, no
• Ways to fix:Engine will need complete overhaul if rod bearings are dead

Camshaft problems

The majority of modern engines have two camshafts. These are the shafts that are located in the engine head and they push the valves to open and close when needed.

While some broken camshafts may make some noises, usually, they die quietly and never really show their problems before the engine stalls. A lot of manufacturers have dozens of recalls and bulletins that are connected with camshafts. And the problem is that modern camshafts have a lot of systems like VTC or VVT - variable valve timing systems.

When a VVT solenoid is failing, it needs cleaning or replacement. Otherwise, the valve timing will be changed and the engine will work harshly. But sometimes the same symptoms may just mean that valves are dirty, especially when it comes to direct-injection engines.

In my opinion, Honda's VTC system is one of the worst in the industry. I've seen literally hundreds of cars experiencing problems with these systems. Also, the BMW Vanos system is not much better and it fails after pretty low mileage.

Camshaft problems highlights:

• Level of importance:Medium
• Commonreasons:Variable valve timing actuator problems, cam bearings issues, overheating
• DIY inspection:Possible but complicated
• DIY repair:Impossible
• Price for repair:$350 - $850
• Can you drive?Usually, yes
• Ways to fix:Clean the VVT (VCT) solenoids, inspect the camshaft, clean the valves

Engine compression problems

I won't take a lot of time talking about compression problems in modern engines because there is almost nothing you can do to fix them on your own.

Usually, the issues are connected with compression rings failure. Also, valves may spoil the compression by not closing completely. Any cracks in the engine, issues with the head gasket, and other problems with the engine's integrity may be the reason for low or zero compression.

You can try injecting some oil into cylinders through the spark plug holes to get the compression back. This will help in cases when the vehicle has been resting for too long and there is no more oil film on the cylinder walls.

Compression problems highlights:

• Level of importance:Medium
• Commonreasons:No oil film, worn-out compression rings, valve issues, cracks, head gasket issues
• DIY inspection:Possible
• DIY repair:Sometimes, possible
• Price for repair:$10 - $2,500
• Can you drive?Only if the engine starts
• Ways to fix:Inject oil into cylinders, check head gasket, check valve system, check compression rings

Cylinder deactivation system problems

A lot of modern engines have cylinder deactivation systems for fuel efficiency and emission control. This means that they turn off two or four cylinders depending on their construction. V8 engines may turn to V4, for example.

But these deactivation systems are pretty faulty and cause a lot of problems. A lot of Dodge owners know about MDS issues because they had to pay for very expensive repairs. Also, there have been tons of issues with Mazda cylinder deactivation systems.

These systems may stop deactivating cylinders. But they may also stop activating them. There are a lot of cases of internal leaks. This is especially bad for big V8 engines that can easily lose all their power and become helpless. Professional repair is only needed.

Cylinder deactivation system problems highlights:

• Level of importance:Medium
• Commonreasons:Internal problems in the system, leaks, electrical issues
• DIY inspection:Impossible
• DIY repair:Impossible
• Price for repair:$250 - $800
• Can you drive?Yes, butthe power may be limited
• Ways to fix:Only professional repair is possible

Engine leaks problems

There are hundreds of various reasons why your engine may leak, but in this article, we are only talking about internal leaks that aren't that visible to car owners.

One of the common internal leaks is gasket problems. Head gasket may start leaking any engine fluid to any inappropriate place. And this needs to be solved as soon as possible.

You may see oil in the radiator or antifreeze in oil, in these cases. And driving your car in this condition after you spot the problem is not safe at all. The engine may be easily blown till you reach your destination.

Also, worn-out piston rings may leak oil directly into cylinders, into combustion chambers. This will lead to the oil level going down without any leaks. Oil rings never make any sounds when they are worn. You will only notice oil consumption.

There are other seals and gaskets that may leak like the timing cover seal. But those leaks may also be external.

Also, intercooler leaks may be internal and hard to spot.

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

Engine lifter problems

Lifters are hydraulic components that allow you to avoid valve adjustment. They adjust the valve gaps when needed. Unfortunately, failure of engine lifters is not that uncommon.

In most cases, you can't locate a broken lifter just by listening to any specific sound that it may make. Professional inspection is needed to understand that this part is faulty. But you can recognize the symptoms of a failed valve position. They are harsh engine work, poor fuel economy, vibrations, stalling, etc.

Hydraulic lifters may fail because of poor oil quality or high viscosity of lubricant. Also, they may stop working because of their age or mileage. They just stop compressing and don't affect the position of the valve.

While in some engines, lifters may tick when they are done, you may easily take this sound for anything else going on in the head or even a block of the engine in your car. So, a professional inspection is needed.

Lifter problems highlights:

• Level of importance:Medium
• Commonreasons:Age, poor oil, too high oil viscosity, mileage
• DIY inspection:Almost impossible
• DIY repair:Possible but very complicated
• Price for repair:$450 - $1,200
• Can you drive?Usually, yes
• Ways to fix:In most cases, replacing the lifters will be the only proper choice

Engine misfire problems

Misfiring means that one or several cylinders don't work constantly or intermittently. They may not get a spark or enough fuel, or there are compression issues, so the combustion process doesn't happen correctly or just doesn't happen at all and it doesn't lead to the piston being pushed down by the explosion.

Your vehicle may misfire and show codes P0300, P0301, P0302, etc. P0300 means that multiple cylinders are affected. P0302, for example, will mean that only the second cylinder misfires. Also, your engine may misfire with no codes. In this case, you will have to check every possible reason to find the solution to your problem.

Also, it's not uncommon for engines to misfire only when cold and then go to normal work. Other engines may start misfiring when you put them under load like towing something or going uphill with some payload.

Driving with a misfiring engine is not a good idea, especially if the misfiring is pretty bad. In this case, you may damage the engine quite fast. So, it's worth going to a repair shop and having the engine inspected as soon as possible.

Engine misfire highlights:

• Level of importance:Medium
• Commonreasons:No spark, electrical problems, no fuel, low fuel pressure, injection issues, compression problems, internal engine damage
• DIY inspection:Possible but very complicated
• DIY repair:Impossible, in most cases
• Price for repair:$500 - $1,600
• Can you drive?Usually, yes
• Ways to fix:Locate the issue and let a professional mechanic fix it for you

Engine noises problems

Engines in vehicles do make noises and it often doesn't indicate a problem. But if you notice that your engine changes its usual noise, this may mean there is an issue that has to be solved as soon as possible.

I've seen a gas-powered Kia Soul sounding like diesel. The problem appeared to be with the crankcase ventilation system but the Kia mechanic told me there are a dozen of other reasons for that sound. Sometimes, the noises are sudden and intermittent like a popping sound that disappears quickly. In this case, it's hard to tell your mechanic what to check.

To diagnose the source of the problem, you also need to understand what circumstances make your engine sound weird. For example, it can change its usual sound when accelerating. I've seen the F-150 truck rattling hard when accelerating and it appeared to be a pretty common issue for these vehicles.

Other engines will sound weird only when loaded. In this case, the problem may not be with the engine itself, you should look at the alternator, engine mounts, drive belt, etc.

Also, does your sound go away with a higher RPM? It doesn't mean that the engine is OK. It only means that a higher RPM balances the engine and you don't hear that weird sound. But it's still there and you should solve the problem. It may sound bad at low speed but be OK at high speed. You just don't hear this when the engine is revved up.

You never know if the bad sound of your engine is actually dangerous. You also don't know how long it will last with this sound. So, have it inspected right now.

Engine noises highlights:

• Level of importance:High
• Commonreasons:All kinds of various problems, hard to list promptly
• DIY inspection:Possible but may be complicated
• DIY repair:Impossible, in most cases
• Price for repair:$150 - $1,000
• Can you drive?Usually, yes
• Ways to fix:Locate the source for the sound and repair the system that needs help

Engine stalling problems

When your engine may stall at times, driving the vehicle is not really safe. This issue may have several sources like electrical problems, engine compression issues, immobilizer glitches, or problems with air or fuel supply.

In most cases, you will also have a check engine light and some codes stored in the ECU when your car dies on the road. By reading these codes, you may easily narrow down the problems and eventually locate the issue.

There is no way a car in good condition would die in the middle of the road. Even if you can restart the engine and drive further, it's a good reason for going to a good repair shop and checking the engine. If this happens to your vehicle once, it may easily happen again. This is a safety consideration due to issues with uncontrollable stalling.

Also, it's not uncommon for a vehicle to die when put in Reverse or when changing the shifter position. In this case, the problem may be with the transmission.

Engine stalling highlights:

• Level of importance:High
• Commonreasons:Compression, electrical issues, fuel or air supply problems
• DIY inspection:Possible but complicated
• DIY repair:Impossible
• Price for repair:$250 - $1,500
• Can you drive?Very carefully
• Ways to fix:It's usually professional repaironlyunless the problem is with the air filter or some other part that's easy to replace.

Engine timing problems

The timing system is responsible for the proper timing of opening and closing valves and also proper piston movement. If something goes wrong, the pistons may bump into open valves and cause really huge engine issues.

Proper timing is ensured by the chain or belt that connects camshafts with the crankshaft. The chain or the belt may jump and change the timing of the engine if they are worn out or old. Also, they may jump if there are issues with the crankshaft, camshafts, or their bearings. Even if they jump just one tooth, the engine will not be able to work efficiently anymore.

Sometimes, timing problems are the consequence of the wrong installation of the belt, pulleys, tensioners, and other parts. But, in most cases, it's all about the old chain or belt that needs replacement and is ignored.

Engine timing issues highlights:

• Level of importance:High
• Commonreasons:Age, mileage, internal engine problems
• DIY inspection:Impossible
• DIY repair:Impossible
• Price for repair:$550 - $1,000
• Can you drive?In most cases, no
• Ways to fix:Replacement of affected parts

Turbocharger problems

One of the important sections of internal engine problems is the set of issues with the turbocharger. Unfortunately, turbos may fail easily without any reason. Some of them just don't have enough quality and will fail at a certain mileage. While some other turbochargers will develop problems because of poor lubrication or very aggressive use.

If your turbocharger experiences abnormal leaks, there is a chance that the seals are not OK. It's possible to repair this without a lot of investment. Just installing a new seal may really help.

If you hear weird turbo noise when accelerating your vehicle, this may mean that something is wrong with the piping. One of the pipes may have gone off and you just need to reinstall it.

It's not uncommon for turbos to develop solenoid problems. There are several electronic units that control the opening and closing of various flaps and gates for proper turbo work. These systems are only reliable for about 80-100 thousand miles. After that, even in a very reliable car, they may fail.

Turbo problems highlights:

• Level of importance:Medium
• Commonreasons:Mileage, age, poor lubrication, internal damage, aggressive use
• DIY inspection:Possible but may be complicated
• DIY repair:Sometimes, possible
• Price for repair:$350 - $800
• Can you drive?In most cases, yes
• Ways to fix:Replace the parts thatare diagnosedto be faulty

Engine vibrations problems

Usually, engine vibrations are obvious when your car is idling. But sometimes, the engine may start vibrating at a certain RPM and this may mean it will shudder at a certain speed. This symptom is very easy to mistake for other problems and give no attention to the engine which will lead to fatal damage soon.

A lot of car owners say their engines shudder when they take their foot off the accelerator. Which may mean there are issues with the transmission or engine. But it may also mean there are problems with shafts and drive system.

Car vibrations when you stop at a red light mean that your engine vibrates when idling. This may be the symptom of misfiring. Also, engine knocking and juddering when you turn it off means that there are issues with fuel supply and air supply which need urgent repairs.

Also, vibrations may occur at very low RPM. This means that the idling speed is too low and you need to adjust it.

Engine vibrations highlights:

• Level of importance:Low
• Commonreasons:Misfiring, engine damage, transmission problems, drive shafts problems
• DIY inspection:Extremely complicated
• DIY repair:Impossible
• Price for repair:$500 - $1,000
• Can you drive?In most cases, yes
• Ways to fix:Only professional repair ispossible,in most cases

Diesel engine problems

It's not uncommon for diesel engines to develop knocking that you won't even hear. This knocking will mask under the normal sound of engine work. Anyway, this is pretty dangerous and may lead to fatal engine damage.

Also, diesel engines have specific parts that may cause issues like the grid heater, for example. There are fuel supply systems that are prone to damage. It's not uncommon for the fuel actuator to show problems of all kinds.

Symptoms of engine problems are different from gasoline engines. For example, a diesel powerplant may start surging and hunting when in trouble. Or it may be knocking way harder than usual when the weather is cold which is also a sign of problems.

Surprisingly, the timing problems are less common for diesel engines as the systems are made to withstand high torque. But still, if you ever see any timing issues with your diesel engine, it's very important to inspect it as soon as possible.

Diesel engine problems highlights:

• Level of importance:Medium
• Commonreasons:Age and mileage, aggressive driving, poor maintenance
• DIY inspection:In most cases, impossible
• DIY repair:Impossible
• Price for repair:$650 - $1,500
• Can you drive?Depends on the issue
• Ways to fix:Replace the worn-out parts, professionalrepair is usually possible only

Common internal engine problems

Some problems are hard to group into the sections I've written about above, so I decided to group them together at the end of this article.

So, there are issues with taking the ignition coils out of your engine. The rubber boot on the coils may get stuck and you may just damage it when trying to get it out.

There are common issues with intake manifolds in almost all modern engines. They may crack and there will be problems with the vacuum and air supply. In this case, your car may freak out and throw various codes.

The important part of mechanics' work with all new engines is the EGR system. It may fail in all different kinds of ways and it may be the reason why your coolant disappears from the tank.

Also, harsh work of the engine is possible when there are issues with the crankcase ventilation system. Sometimes, you can even fix it on your own. This may even be mistaken for timing problems, ignition issues, etc. If not fixed, this may lead to the engine locking up and failing fatally.

Of course, the issues with a lot of smoke from the tailpipe are still very common. White smoke means antifreeze burning, black smoke is the symptom of poor combustion of fuel, and grey smoke means burning oil. In diesel engines, you should check fuel pressure when you see a lot of smoke.

Older carbureted engines are notorious for carb problems, but there are also issues with the timing of the distributor which is the number two popular issue with such engines.

Internal engine problems highlights:

• Level of importance:High
• Commonreasons:Mileage, poor maintenance, improper use, physical damage
• DIY inspection:Possible but may be complicated
• DIY repair:Possible, in some cases
• Price for repair:$250 - $1,500
• Can you drive?Depends on the issue

• Ways to fix:Locate the problem, outline possible fixes, replace or repair the worn-out parts