An exhaust manifold is the first component of a car’s exhaust system. Its purpose is to direct fumes emitted by the engine cylinders down and out through connected pipes to the muffler.
Since the exhaust manifold is one of the first components to handle the hot and highly pressurized fumes from the engine, it is often liable to damage. Cracks are common, especially in older models.
The average exhaust manifold repair cost can vary depending on the cause of the damage and how extensive the damage may be. Here, you will find out how an exhaust manifold can fail and how much it might cost to repair or replace it.
How much does an exhaust manifold repair/replacement cost?
Finding out exactly how much your exhaust manifold repair cost is can be frustrating. Without going to see a mechanic, it’s challenging to get an exact number on how much your repair will be.
While each case is different, you can expect to pay between $150 and $1200, with the average cost falling in the range of $200 to $400.
Read more about exhaust leak costs.
How long does it take to replace a manifold?
The exhaust manifold is next to the engine, making it quite tricky to repair. Getting inside and removing some other parts may be necessary to get at the manifold. As such, it can take anywhere from three to five hours to replace or repair one.
Sample Prices to Repair
We will now look at a few different sample prices for different repairs.
Patching a leak in an exhaust manifold typically requires welding. While this isn’t a permanent fix, it will stop the leak. You can expect to pay between $125 and $250 for labor, and $15 to $50 for parts, for a total of around $140 to $300.
Replacing an exhaust manifold can be very expensive. For labor and a new manifold, you can expect to pay around $1000.
The brackets that hold a manifold in place tend to break down. Getting these fixed may require welding of the exhaust manifold as well as replacing the part. For this, you can expect to pay around $300.
How long do exhaust manifolds last?
A new and correctly installed exhaust manifold should last the life of your car.
The biggest impact we’ve seen to the lifespan of manifolds of is rust. So if you live in the rust belt, or drive on salted roads, you may be replacing your manifold and entire exhaust around 60,000-100,000 miles.
If you’re towing or racing, all bets are off. Guys in the ‘Tuner Crowd’ are constantly swapping manifolds to squeeze that last bit of power out of their engines. If you know the word, Cobb, there’s a high likelihood you’ve replaced your manifold (by choice) 🙂
What causes damaged exhaust manifolds?
Heat is the leading cause of damage to exhaust manifolds. The constant cycling of heat between the engine and the exhaust takes its toll over the years. Cracks will form along the manifold over the years that can compromise the manifold’s ability to deal with pressurized gases.
The other common type of damage mechanics find in exhaust manifolds are leaks. Heat is also the main cause, but affects the gasket that seals the gap between the manifold and the engine block instead of the manifold itself. When the gasket expands and contracts during heat cycles, the seal eventually wears thin or comes loose. Liquids can then seep out, affecting the performance of the vehicle.
AAMCO Minnesota has some more information on what causes damage to the exhaust manifold, along with some symptoms of damage.
How hot do exhaust manifolds get?
The temperature for exhaust manifolds will vary depending on the vehicle’s make and model. During regular operation, the exhaust manifold is usually around 300 – 600°F. However, the maximum you can expect it to reach is upwards of 1200 °F when the vehicle is under intense stress or the manifold is leaking.
If your exhaust manifold is operating above 1000 °F, there is typically a problem. An EGT gauge will help you monitor your temps.
Can I drive with a damaged exhaust manifold?
We highly recommend that you fix your damaged exhaust manifold before you drive your vehicle again. A cracked or leaking exhaust manifold will release heat and highly pressurized gas to surrounding parts, damaging and even melting or igniting fuel and wiring.
When your exhaust manifold fails, it’s not only dangerous for your car, but you as well. A critical car part failing can cause you to get into an accident. Even if the vehicle can turn on and operate, you shouldn’t drive it before getting the exhaust manifold repaired.
If you drive with a damaged exhaust manifold, the best-case scenario is that it causes damage to other components, increasing your repairs’ total cost. Worst case scenario is it auto-ignites the fuel, resulting in a fire or even an explosion.
How Does an Exhaust Manifold Leak Sound?
Since a damaged exhaust manifold is releasing gas, the sound it makes is akin to air escaping through a small hole in a balloon. You may notice a hissing sound or rhythmic tapping, especially during acceleration or when you cold-start the car.
Intake Manifold Crack Symptoms
Your car also has an intake manifold, which brings in fresh air to regulate its internal temperature and keep the engine running at peak performance. When your intake manifold is damaged or failing, you may experience the following symptoms:
- Rough idling
- Milky engine oil
- Leaking coolant
- Quick engine overheating
What are some other exhaust leak symptoms?
You might notice other things wrong with your car in addition to the exhaust leak symptoms listed above. There may be a problem with your exhaust manifold if you experience:
- Decreased fuel efficiency
- Loud engine noises
- Low power on a turbocharged engine
- Irregular gas pedal vibrations
- Check engine light
While the check engine light signals a problem with the exhaust manifold, it can also indicate issues in other parts of the vehicle. It is essential to have a mechanic check out your car if the check engine light goes on, no matter what you might think the problem is. Doing this early on may reduce your exhaust manifold repair cost.
If you’re handy with a wrench, an Android or Apple OBD2 Scanner will help you pull DTC’s. Some common ones for exhaust you may see are P0471, P0014, and P0141
We hope this article has helped you find out how much your exhaust manifold repair cost might be. While different mechanics will give different appraisals, you can expect the price to be no more than $1200, depending on the issue. Of course, the first step is diagnosing the problem; and Scanner Answers can help with that!