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How to Tell if Your Exhaust Manifold is Leaking?


How to Tell if Your Exhaust Manifold is Leaking?

 If you’ve ever had issues with your car’s exhaust system, then you know how crucial it is to get these problems diagnosed and fixed ASAP. Specifically, a leak in the exhaust manifold is dangerous and can cause more vehicle damage, so how do you tell if you even have a leak in the first place?

The most common symptoms of an exhaust manifold leak include a check engine light illuminated in the dash, strange noises when turning the ignition, poor gas mileage, difficulty accelerating, fumes in the cabin, and burning odors.

To learn more about the specific smells, sounds, and visual cues to look for that may indicate an exhaust manifold leak, keep reading. This guide will also give you a comprehensive look at the risks of this auto leak and answer frequently asked questions about it. Now, let’s get into the specifics!

What Is an Exhaust Manifold?

A car’s exhaust manifold is an essential part of the exhaust system that transports exhaust gas from the engine to the exhaust system (catalytic converter) and eventually out of the vehicle. In fact, it’s the first part that the gas reaches after leaving the engine, as it’s connected to the engine block.

These heavy metal components are partly responsible for keeping you and your passengers from inhaling toxic exhaust fumes while operating the vehicle. You may have either one or two exhaust manifold pieces in your car, depending on its exhaust system design.

Sometimes, though, the manifold can become compromised due to normal wear and tear, such as cracks, warps, and bad seals. These issues unfortunately lead to exhaust leaks, which are very dangerous to drive with and can even funnel the gas into your car’s cabin where you breathe.

Read: How Much Is an Inspection for a Car?

Risks from Exhaust Manifold Leaks

You may be wondering how do (or can) you temporarily fix an exhaust manifold leak? The truth is that it’s not a great idea to try and temporarily fix this issue. It’s going to need almost immediate attention and a long-term solution to ensure your safety and prevent further damage to other engine and exhaust parts.

The thing is that there are several risks to exhaust manifold leaks, especially if you let the issue go on longer than you should.

Fumes in the Cabin

One of the most dangerous risks you take when you don’t fix the leak is the possibility of letting exhaust fumes get into your cabin. If this occurs, you could be breathing in toxic gas, even if you roll your windows down. The dangers of this include carbon monoxide poisoning, which can be fatal.

Engine Damage

If you let an exhaust manifold leak continue, it could damage the engine cylinder head since they are connected. This is a costly risk to take since the average cost to replace an engine cylinder head is about $3,600 ($1,350 for labor and $2,250 for parts).

Exhaust System Damage

Furthermore, a manifold leak could cause damage to other parts in the exhaust system, such as the catalytic converter or the exhaust valves (these often burn due to exhaust leaks).

This damage can also be a costly risk since the average cost to replace a catalytic converter is about $1,885 ($165 for labor and $1,720 for parts).

Read: How To Tell If a Catalytic Converter Is Clogged

Ways to Detect Exhaust Manifold Leaks

You may be curious: how serious is an exhaust manifold leak? This is one of the more serious leaks you can have in your car since it actually puts your health at risk. While an exhaust manifold leak is unfortunately going to need immediate repair, you can at least be aware of the signs so you can detect it sooner rather than later.

Engine Check Light

Most modern car dashboards have a check engine light that looks like a small engine. This light will illuminate when there is an issue with the engine, such as an overheated engine, a lack of engine oil in the reservoir, etc.

If the check engine light comes on in your dash, it could be a sign that the exhaust manifold is leaking. But you’ll probably need to observe other issues in combination with the light, such as odors or noises when starting your car.

Strange Ignition Noises

Another sign of a leaky manifold that is more obvious is a rattling or abnormal noise that persists when you start your engine (or when you’re driving).

These noises may intensify when you try to accelerate. These noises are the sounds of exhaust gas escaping from the manifold before it gets to the converter.

Read: 5 Reasons Why A Car Engine Knocks On Startup Then Goes Away

Bad Gas Mileage

Another indicator of a leaky manifold is a sudden drop in engine performance, which often causes your gas mileage to drop as well. If you’re continuously getting lower fuel efficiency, it’s likely because your car is not properly using fuel since the oxygen sensor is compromised by the leak.

Difficulty Accelerating

As previously mentioned, a leaking exhaust manifold will compromise your engine’s performance. As a result, you’ll likely notice that the car isn’t speeding up as quickly when you use the gas pedal.

Cabin Fumes

This is the most obvious sign of an exhaust manifold leak, and you should always take it as a sign to get your car to a repair shop ASAP.

The smell of exhaust gases in your cabin is a sign that the manifold is leaking exhaust and it’s getting filtered in through your vents. It will have the smell of carbon monoxide or be smoky/musty.

Burning Smells

One other common sign of a leak is a noticeable burning odor that comes from your engine. This is because the exhaust fumes aren’t leaving the cylinder(s) quickly enough and are overheating these parts, even burning them in some cases.

Final Thoughts

Hopefully, our article detailing how to tell if your exhaust manifold is leaking has been helpful to you. The most obvious signs include burning engine smells, cabin fumes, and check engine lights, among others.

Make sure to get this leak fixed as soon as possible to avoid other costly damage and danger to you and your passengers.

Read: What Are Jeep EcoDiesel Problems?


Can you drive with a leaking exhaust manifold?

You can technically drive with a leaking exhaust manifold, but you really shouldn’t unless it’s just a short drive to the mechanic to get it fixed. This leak can cause exhaust fumes to leak into the cabin, which is toxic to breathe and can even kill you in worst-case scenarios. Further, it makes your car much more dangerous to operate since it compromises the health of the engine.

How much does it cost to fix an exhaust manifold leak?

Depending on what parts you get repaired or replaced, costs vary. But generally, it will cost anywhere between $150-$350, based on average auto labor rates and the few hours it takes to repair this issue. Note that if you let the problem persist and it damages the engine or entire exhaust system, repairs may cost even more. 

What happens if you don’t fix an exhaust leak?

If you have an exhaust leak and don’t fix it as soon as possible, it could lead to further damage to your engine, catalytic converter, and even the cylinder head beneath the hood. Over time, these issues add up and lead to compromised vehicle performance.

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