4 Signs You're Driving with a Cracked Exhaust Manifold

Automotive Blog

Your car's exhaust system is one of its most vital parts, and it's actually made from several different components. One is the exhaust manifold, which is responsible for collecting the fumes generated by the engine and channelling them toward either the catalytic converter or turbocharger, depending on your vehicle.

The exhaust manifold is the first part of your exhaust system, which means it is subject to high thermal stress. Most are designed to last for the life of a vehicle, but they can still develop cracks. When this happens, you'll want to have your vehicle serviced as soon as possible.

With that in mind, here are just four common signs of a cracked exhaust manifold.

1. Strange Engine Noises

When cracks develop in an exhaust manifold, you're likely to hear strange noises coming from beneath the hood as gases are forced out at high pressure. The exact sounds produced can differ depending on where cracks form and how much pressure gases are under, but you may hear whistling, clicking, hissing, or tapping sounds. It's generally easier to hear those noises when the engine is still cold, so any strange sounds that occur when you first start your engine are likely due to a cracked exhaust manifold.

2. Strange Smells

When exhaust gases are allowed to leak out of a cracked manifold, they should stay in the engine bay rather than being directed into the cabin. That said, you may still notice exhaust smells or gasoline smells in your cabin. If you do, it's important to have your vehicle checked as soon as possible since any exhaust gases in the cabin can be extremely dangerous.

3. Poor Performance

The pressure created by your exhaust system does more than expel the exhaust gases themselves. Your engine also uses backpressure from those gases, and backpressure is reduced when cracks develop in the exhaust manifold. Since your engine won't be performing properly, you may experience sluggish acceleration or an overall drop in power. This is often especially noticeable when you try to accelerate when you're already driving at high speeds.

4. Reduced Fuel Efficiency

When exhaust gases are allowed to leak from the manifold, your vehicle's oxygen sensors are no longer able to take accurate readings. This often means the vehicle's electronic control unit (ECU) will try to compensate for a lean fuel/air mixture by increasing the amount of fuel sent to your engine. This means you may suddenly find yourself travelling fewer miles than you used to on the same amount of fuel. 

For more information about car services, contact a local company. 


7 March 2023