Ownership of a car is a big responsibility. Cars are somewhat like high performance machines that are difficult to get the appropriate wear and tear (in regular intervals) expected out of them.
You need to perform regular maintenance on a car, and a really important aspect is to maintain its engine. It is usually recommended to get your oil changed relative to shedding 3,000-5,000 miles. If you can properly maintain oil in a car, it may prolong the life of your car engine.
Of course, there are many other things to do to maintain a car engine, but keeping oil levels in check can be the separating factor between needing a few minor repairs and needing a complete engine replacement. If you do not maintain your oil, it is likely to create internal damage, and the worst scenario can be complete engine seizure.
Understand the symptoms of a seizing engine to be able to spot issues sooner rather than later, potentially preventing permanent damage to your engine.
Locked Up Engine vs Seized Engine
These two terms are often used interchangeably, but they actually do mean two different things – while they may cause some of the same symptoms, the cause of the issues and the price of repairs can be quite different.
A locked-up engine is when something is physically restricting the engine from turning such as a broken or bent part. While it doesn’t rotate right now, this means the engine can be repaired and made operational again.
A seized engine on the other hand, is when the internal pieces of the engine sustained major damage, such as bearings fusing the crankshaft, or the pistons seizing themselves within the cylinders.
Generally, a seized engine is a result of overheating, or lack of lubrication and is generally more difficult and expensive to repair compared to a locked engine.
Seizing Engine Symptoms
The good news is, a seizing engine does not mean it is completely doomed to destruction. There are some early symptoms that you should recognize as warning signs.
If you can see them in the early stages of the issue, you may be able to have the vehicle towed to a garage and have mechanics fix the problem before it creates more mechanical issues for the engine.
Here are the top 3 symptoms of a car engine seizing up.
#1. Oil Light On.
If your engine components are locking up, it can hault the circulation of oil. Your engine control unit will notice the oil is not flowing properly and knows something is going wrong.
The engine control unit will engage the engine oil warning light on the dashboard because of this. Some vehicles use this same warning for the check engine light so you may see one or both lights in your dashboard.
#2. Poor Acceleration (or none at all).
An engine can not seize up and run, as a vehicle drives. When your engine is about to seize, you can tell the performance of your engine is diminishing, usually by a lot.
So, each time you step on the gas pedal expecting to accelerate your vehicle, with a seizing engine, you may not be able to accelerate at all, and it is likely that this acceleration will be sluggish.
It will get to a point where your engine is locked up, and your car will come to a stop permanently.
#3. Knocking Sounds.
In a seizing engine situation, the piston rod is knocking against the crankshaft. It will do this repeatedly, and you will hear knocking sounds. The sounds will continue to get louder and worse unless you isolate the problem very quickly.
Reasons Why an Engine May Seize or Lock Up
Lack of Lubrication
One of the leading reasons behind engine seizure is lack of lubrication. Engine parts like the pistons, crankshaft, and cylinder walls need regular oil circulation to keep their heat and friction at a minimum.
When these parts are removed from the oil or there is a failure of the oil filter that leads to oil starvation, parts will grind against each other. The friction increases, thus causing heat, followed by a seized engine.
The two most important things as an engine owner they could do regularly would be checking their engine oil level and changing their oil filter when necessary.
Overheating and Heat Damage
Another leading cause of a seized engine is overheating. An engine can suffer from overheating due to many reasons: too little coolant, a defective cooling system, and extreme temperatures.
When an engine overheats, the heat causes a significant amount of the moving metal engine parts to expand to the point of causing friction and failing piston rings that can damage the pistons and cylinder walls.
The amount of heat and friction can actually cause metal parts to fuse or weld onto one another, and this will cause a seized engine.
An operational cooling system and checking proper coolant can minimize the possibility of engine seizure or overheating.
Water and Hydrolocking
Lastly, water entering the engine can also cause an engine to seize. This could occur by water ingestion through an air intake or even an internal water leak. This condition is known as hydrolocking.
Since water cannot compress like fuel or air, water that enters the engine cylinders will prevent pistons from moving within their cylinders creating a hydrolocked engine.
Getting back to, hydrolocking is not to be confused with vapor lock because vapor lock can be remedied by letting the engine cool down, hydrolocking can create serious damage to engine parts: bent connecting rods or even a cracked engine block.
In order to avoid hydrolocking your engine, one should be careful when driving through standing water and checking the seals and intake valves for signs of damage or leaking.
Also, keeping up with regular engine maintenance, such as spark plug replacement and engine inspections will help from hydrolocking your engine.
Can You Fix a Seized Engine?
When a mechanic declares an engine to be “seized”, there are not many options for the owner of the vehicle.
In most cases, the owner will be utilizing either new or used engine replacement parts – if there is significant internal damage to the engine, an engine replacement will be either recommended or necessary.
While it is possible to fix damaged engine components and have a machine shop fix the engine block, the cost of rebuilding the engine is usually going to be more than simply replacing it.
The exception would be if you have certain “high-performance” or rare engines (which will be expensive regardless of the direction).
There will be times where the reason for the engine lock up may simply be from the vehicle just sitting too long, and being exposed to the elements.
In those cases, you may have a salvageable engine. This is why it is important to work with a professional (mechanic) that you trust.
Seized Engine vs Bad Starter
A bad starter can lock up, confusing it with a seized-up engine. You want to be sure that the mechanic makes the proper diagnosis because the two can have similar symptoms.
Generally, the mechanic will try to rotate the crankshaft by hand first to confirm that your starter is not an issue.
If the crankshaft does rotate, the issue is likely the starter. If it does not, the next step might be to remove the starter and check again whether the crankshaft can be moved.
How Does a Mechanic Confirm a Seized Engine?
When a mechanic confirms whether an engine is seized, the first item checked is whether there are any external obstructions or damage.
If that is clear, the next step is to try to rotate the engine by hand with a breaker bar or wrench to determine if it rotates at all or is extremely stiff.
If unable to move or goes very stiff, the diagnosis would be a seized engine.
A mechanic will also look to see if there are any warning signs such as, low oil pressure, empty coolant reservoir, or burn smell.
An additional check may also include a compression test or an endoscope to determine internal engine condition.
Can an Engine Seize With Oil In It?
Yes, it is possible for an engine to seize, even when there is oil in it, if the engine oil system is not operating correctly.
For example, if the oil passages are blocked from sludge buildup or if the oil pump is bad, oil flow will not reach critical moving parts, causing friction, overheating, and likely, a seized engine.
Additionally, wrong oil type, infrequent oil changes, and running low on oil can all contribute to a seized engine. Make sure to regularly check and maintain vehicle oil levels and quality to prevent seizure.