You don’t have to be a petrol-head to be able to identify most basic parts of your car. Even children know stuff like tyres, steering wheels and engines, and as an adult, chances are that you can recognise your gearbox, brake pads and spark plugs by sight too. But one component you might not be so familiar with is your car’s catalytic converter. So as experienced specialist Chrysler breakers here at ACD of Lancashire, we’ve provided a quick breakdown of everything you need to know, and how to tell when yours might need replacing.
What is a catalytic converter?
Sometimes known simply as a cat, it’s a critical component in your vehicle’s emissions control systems. Its primary job is to capture all the particularly toxic gases from your car’s combustion engine, and convert them into harmless compounds.
Originally developed in the 1950s for use on chimneys and smoke stacks, catalytic converters ultimately made their way over to vehicle manufacturing. For maximum efficiency, they typically need to work at incredibly high temperatures of around 400°C. To this end, in their early days they were generally positioned very close to the engine, but these days you’ll find them underneath the car, down towards the exhaust outlet.
How does a catalytic converter work?
Catalytic converters use a honeycomb-like structure of metals to filter out the most harmful elements in exhaust gases from your engine. These exhaust gases include:
- Hydrocarbons (generally in the form of unburned petrol)
- Carbon monoxide, formed when the petrol combusts
- Nitrogen oxides, created by the heat from the engine
These are all pushed through this honeycomb structure, which consists of a core of ceramics riddled with pores less than 1mm in diameter. These pores are coated with powdered catalysts containing precious metals like palladium, platinum and rhodium.
When the car is in motion, these are heated up to significantly high temperatures, which changes the chemical structure of the gases passing through them. That turns carbon monoxide into carbon dioxide, nitric acid and nitrogen dioxide down into nitrogen gas and oxygen gas, and hydrocarbons into harmless water vapour.
Catalytic converters should generally last about ten years, but as with any car component, their exact lifespan is dependent on how frequently and intensively the car is driven.
How to know when your catalytic converter is failing
Your catalytic converter is a fairly critical component to the overall functioning of your vehicle, which means that your car will generally give you some pretty obvious warning signs of when it starts to fail.
- You might experienced reduced acceleration, or your car might not accelerated past a certain RPM (often idle speed)
- Your engine runs roughly or sluggishly, or cuts out entirely (due to additional back-pressure)
- Dark smoke from your exhaust
- Increased fuel consumption
- A noticeable smell of rotten eggs – sulphur – coming from your exhaust
- A notable increase in your emissions
One big problem can be excessive unburnt fuel in the exhaust, which can cause the catalyst to get to very excessively high temperatures. That can ultimately cause damage to the fine catalyst material, which will have a serious impact on its ability to effectively filter out exhaust gases.
And rapid cooling of the cat can damage it too – say, if it’s suddenly submerged in water. That can cause the honeycomb structure to break up, and obstruct the exit to the exhaust. That can obviously cause some major damage to your engine, so if you think that’s what has happened, don’t drive your car for another metre further than you absolutely have to, and get it to a garage as soon as you can.
To reduce the risk of damage to your catalytic converter, try to avoid using leaded fuel, and make sure to check your fuel injectors so that your cat doesn’t get blocked or fouled. Misfires and bump starts can also be harmful in the long term, as they can cause unburnt fuel to damage the catalytic converter – eventually beyond repair.
Why do catalytic converters get stolen?
Catalytic converters are attractive to thieves because of the precious metals they contain. Palladium, rhodium and platinum are all relatively rare materials, and generally recycled when the car is scrapped. There’s an increasing demand for these precious metals in overseas markets, which is a large part of what’s driving their frequent theft from UK vehicles.
If you’re worried about your own catalytic converter getting stolen, there are a couple of things you can do.
- Keep your car in a locked garage if you can, or in a well-lit area with lots of foot and road traffic coming and going. Very few thieves will risk doing the job with an audience
- Park your car close to fences, walls or kerbs. If you can, try and avoid parking it half on the pavement and half on the road, as this can make it even easier for thieves to access it
- There are a variety of aftermarket commercial devices you can choose, such as a cage clamp, which can make it far more difficult for thieves to remove your catalytic converter. Alternatively, you can choose a Thatcham-approved alarm to deter would-be thieves.
- If your catalytic converter has been bolted on to your car, you might want to ask your local garage to weld the bolts on, which will make it trickier to take off.
With any luck, your catalytic converter should give you a good decade or so of use. But if you ever need a new or replacement catalytic converter, you’re in exactly the right place. As specialist Chrysler breakers here at ACD of Lancashire, we provide a comprehensive range of parts and components, including catalytic converters, so you can always keep your car in top condition. If you’re having trouble finding something you need, don’t hesitate to let us know on 01254 301021, and we’ll be happy to see how we can help.