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Identifying Bad Exhaust Symptoms and What they Mean

bad exhaust symptoms

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Identifying Bad Exhaust Symptoms 👀👂

No matter what kind of car you have, and regardless of the type of exhaust system on your vehicle, if you have problems with your exhaust, it can affect your car’s performance. Some problems are quite easy to find and repair, whereas others need professional assistance. There are several bad exhaust symptoms to keep an eye, and ear, out for.

Note: Make sure you allow adequate time for the exhaust system to fully cool down before performing any inspections or repairs yourself.

1. Rust on the Exhaust Pipe

Rust is a fairly common problem on exhaust pipes and mufflers. You can typically see discolored patches and notice an uneven texture. Rust is typically caused by condensation. After use, as the exhaust system is cooling down, moisture in the air can cause condensation.

It’s important not to ignore rust, as the problem will become worse over time and could create holes in the pipe.

If there’s a minimal amount of rust, you can usually clean it off by yourself. Mix a solution of white vinegar and salt, soak a piece of old cloth in the liquid and then wrap it securely around the rusted area. Leave it in place for as long as possible. The acid in the vinegar will loosen rust, meaning you can rinse it off with water. If the rust is stubborn, you can use a wire brush to gently scrape it off.

2. Loud Noises from the Exhaust

Unusual sounds from the exhaust system typically indicate a problem. Noises may sound like whirring, buzzing, humming, growling and similar.

There are several causes of noises, but one of the most common is a hole or crack in the exhaust pipe or muffler. Generally, the closer to the engine the hole is, the louder the noise.

Holes may be caused by rust. Exposure to salt can also cause holes; people who live near the coast may experience this problem more frequently. Frequently driving fast over potholes and speed bumps can also crack the exhaust.

On inspection, if you can see a small hole in your exhaust pipe it is often possible to patch it up yourself. There are a range of easy-to-use repair kits for patching up exhaust pipes, including self-sealing tapes, metal bandages, silicon bandages and hard-drying putties. Some people cut a piece of metal from an aluminum can and affix it over the hole as a temporary measure, and you can fashion emergency repairs using a can and some wire.

If you cannot easily see holes with a visual inspection, ask a friend to start your safely jacked-up car and carefully look underneath for small wisps of smoke exiting from holes and/or cracks.

3. Banging Noise Under the Vehicle

If your car is making loud banging or clanging noises from underneath, it could be a sign that an exhaust hanger has broken or worked loose. You may also notice parts of the exhaust system dragging along the road.

Also known as a muffler strap, the hanger is made from rubber and so does eventually suffer from wear and tear.

You can remove the old exhaust hanger and affix a new one yourself.

4. Rattling Noise Under the Vehicle

When running but not in motion, loud rattling noises from underneath the vehicle may suggest that there is a serious issue with the catalytic convertor.

While there are various ways that you can check your catalytic convertor, any issues signal that you’ll need to have it replaced.

5. Decreased Acceleration

If your car is slower to accelerate and feels sluggish when you press the gas pedal, this can be due to an exhaust system problem. You will probably notice this more when trying to accelerate from a stationary position.

Poor engine performance can be caused by leaks. Depending on where the leak is in the system, you may be able to fix any holes or cracks as in point 2.

6. Misfiring Engine

A misfiring engine refers to times when you try to start your car but it doesn’t work as it should. This is caused when not enough power is produced by one or more cylinders. There can be several causes for this, including worn out spark plugs, leaks in manifold gaskets, vacuum leaks and failure of ignition coil pack.

Engine misfires can, however, also be a symptom of a bad exhaust system. Misfiring occurs when there is some obstruction in the emissions system that doesn’t allow gases to leave as they should. You can check for blockages using a pressure gauge.

If your engine is misfiring due to blockages in the exhaust system, you will need to have a new muffler fitted. You may alternatively need a new catalytic convertor.

7. Increased Fuel Consumption

Exhaust problems can lead to increased fuel consumption, or a reduction in fuel efficiency. While there are several possible causes for fuel consumption to go up, exhaust issues put more pressure on the engine and so burn through more fuel.

This is generally caused by leaks in the exhaust system, due to cracks and holes. See point 2 above for how to undertake DIY car repairs.

8. Unusual Smells

In short, the job of the exhaust system is to remove fumes safely from the engine. Any issues within this system can cause gases to escape, resulting in strong smells.

You may notice a burning smell when there is an issue with the exhaust system as leaks in the manifold gasket can cause nearby car parts to burn. Fortunately, replacing the manifold gasket yourself is relatively easy. Loosen the bolts to remove the old gasket and replace with a new one.

If you can smell exhaust fumes outside of the car while the engine is running, possible causes include leaks and a failing catalytic converter.

If you can smell exhaust fumes inside the car, you should seek professional guidance as soon as possible. Toxic fumes can be hazardous to health.

Keep Your Car Running Smoothly

Now you know the ins and outs of potential problems with your exhaust system, what about other parts of your car? Sign up for Treads tire subscription service for peace of mind and convenience when it comes to your wheels.

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