Every internal combustion engine has a certain number of cylinders in it. These cylinders have cylinder heads on top of them. Once the cylinder heads are closed by the pistons, the air and fuel mixture is compressed within the combustion chamber. This is necessary for a successful ignition to take place. If the cylinder heads were to suffer damage or wear and tear, then it’ll interfere with the entire combustion process.
The construction of cylinder heads does not use the most durable materials. In fact, cylinder heads are made to be lightweight on purpose by their manufacturers. Unfortunately, this makes them easily prone to damage caused by wear and tear. After about 5 years or so, the cylinder heads start to form cracks in their aluminum material. Most vehicles made within the last 20 years have aluminum cylinder heads, so this is to be expected. The only exception is if you have an older vehicle with iron cylinder heads. Then the heads may last longer.
5 Common Symptoms
A cylinder head crack will cause symptoms to emerge in your vehicle. Once you figure out what these symptoms mean, you can immediately take steps to repair the cylinder head crack. Below are the top 5 symptoms of a cylinder head crack.
1) Leaking Oil
Oil is inside of a cylinder head. Obviously, a cracked cylinder head will cause an oil leak. This can be verified if the oil warning light is activated by your engine control unit. As soon as you see this light turn on, check your cylinder head to see if there is a crack.
2) Leaking Coolant
In addition to oil leaking out of the cracked cylinder head, you may see coolant leaking out too. This will overheat your engine quickly, resulting in the needle of the temperature gauge moving toward the red zone on the dashboard. You need to quickly check your coolant levels and look for evidence of a leak if the coolant levels are low. Repair the cylinder head and add more coolant as needed.
If your cylinder heads have extra big cracks in them, then exhaust gases will find their way out quickly. As a result, your engine will become very smoky. You will clearly be able to see this smoke coming from the hood of your vehicle. You must replace your cylinder head as fast as possible to stop this problem from getting worse.
4) Bad Engine Performance
A bad engine performance is one of the first symptoms you will likely notice from a cracked cylinder head. Because of the crack, the compressed air can get out of the combustion chamber. This will cause a rich fuel-air mixture, where there is more fuel than air in the mixture. The engine cannot perform properly with this type of mixture.
5) Misfired Engine
As the engine performance gets worse, engine misfires will present themselves. You’d be lucky if successful combustion can even happen in the chamber if the cylinder head is cracked. Often times, the engine will stall as you’re driving or fail to fire up altogether. You’ll have no choice but to repair the cylinder head in this case.
- 5 Causes of Car High Fuel Consumption in Petrol and Diesel Engines
- 5 Symptoms of a Bad Vapor Canister Purge Valve in Your Car
- Difference between Rich vs Lean of Air-Fuel Mixture Ratio in Your Car
If you have a cracked cylinder head, then you’ll need to get it repaired promptly. The repair cost of a cylinder head crack is $500 at a minimum. This price factors in both the parts costs and labor costs too. Of course, the make and model of your vehicle plays a huge role in determining the repair costs. For instance, if you have an older vehicle with an iron-based cylinder head, the parts costs alone will be $500. Then you’re looking at another $500 for the labor costs too, which brings the total to $1,000. But if it’s a newer vehicle with an aluminum-based cylinder head, then it will be about $500 total to repair it.