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Signs of a bad Catalytic Converter: Man checking Engine

4 Tell-Tale Signs You May Need a Catalytic Converter Replacement

Your catalytic converter plays a vital role in reducing the emissions of your car, by turning harmful chemicals into water vapour and other gases. You’ll find it near the exhaust manifold, and it will typically last for 7-10 years before it needs replacing. 

Like most car parts, over time your catalytic converter will likely deteriorate, meaning you’ll need it replaced by specialists, such as ourselves. Typically this will be caused by carbon buildup over time, overheating or contamination. 

Frustratingly, unlike other areas of your car, an underperforming catalytic converter won’t show as many obvious signs, especially in the early stages. You need to be aware of any indicators to highlight the problem to minimise the damage. Alternatively, we can do this for you.

To make sure you’re aware, we’ve made a list of faulty catalytic converter symptoms that indicate you should book an appointment as soon as possible. 

Let’s get started!

1. The Check Engine Light is On

Signs of a bad Catalytic Converter: The Engine Light Indicator

If you’re facing a potential catalytic converter failure, then the “Check Engine” light may illuminate on your dashboard. This is because most modern vehicles have oxygen sensors that can detect your catalytic converter’s efficiency.

However, it should be noted that this light can indicate many other issues, not just a failed catalytic converter. If your check engine light has come on, our technicians may be able to conduct a visual check to identify the problem, but in many cases, will require further diagnostics. At any rate, it’s better to have someone take a look sooner rather than later.  

For peace of mind, book your diagnostic appointment at our garage and our technicians will uncover the issue.

2. Decreased Miles Per Gallon

When you have a clogged catalytic converter, your engine receives less airflow. This causes your vehicle to burn more fuel, and your decrease miles per gallon. As a result, you may notice more fuel refills, particularly on longer drives. 

If you notice your vehicle is burning through fuel more rapidly than usual, it may be worth having an expert take a look.

Even if your catalytic converter isn’t the issue, this is a symptom of other potential issues with your car. If you notice worse fuel mileage, contact us immediately and we’ll take a look at your vehicle and check for any issues.

3. Poor Acceleration

Signs of a bad Catalytic Converter: Car Acceleration!

One of the most common symptoms of a faulty catalytic conductor is engine power. This may lead to difficulty, or reduced performance, whilst accelerating.

This is primarily due to additional carbon buildup or high temperatures from unburned fuel. In severe cases this can cause internal components of your engine to melt, leading to further blockages within the catalytic converter. 

All this in turn can lead to reduced acceleration and, in the worst cases, make it impossible to drive uphill or travel with more weight than usual. 

If you’ve noticed your vehicle is more sluggish, it may be time to get in touch with our experts. 

4. Dark Smoke or Sulphur Smell

One of the most obvious signs your catalytic converter needs attention is dark smoke coming out of your exhaust. This may be accompanied by the smell of sulphur, not dissimilar from rotten eggs.

Like many of the other signs, this may not immediately indicate an issue with your catalytic converter, but is a sign that you’ll want to get your vehicle checked out as quickly as possible.

Bonus: Failing an MOT Test

It may not be a tell tale sign, but it’s worth a mention. A bad catalytic converter is one of the most common reasons for failing your MOT test. 

MOTing more than 10,000 cars a year, if your car is unlucky enough to fail it’s MOT, you’ll be in good hands to have it repaired by In Town Automotive as quickly as possible.

Book Your Catalytic Converter Diagnostic or Replacement Today

If you’re based in Northamptonshire and you’re in need of a car diagnostic or repair, then In Town Automotive is the place to go. As one of the largest independently owned vehicle service and repair garages in Northampton, we’re well equipped to have your car repaired professionally and quickly.

We have a large team of experienced technicians who offer advice and repairs for your vehicle. Additionally, if you need replacement parts, we have a full range of high-quality parts to ensure your vehicle runs smoothly.

Conducting MOT tests at affordable prices, we keep your car in safe, legal, road worthy order. You can book an appointment online with us by calling 01604 666 700 now!

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