Question 1

What does a catalytic converter do?

Accepted Answer

A catalytic converter is a key component of your exhaust system. It changes harmful substances in a car’s exhaust gasses, such as carbon monoxide nitric oxide, and hydrocarbons, into less harmful gases, such as water vapour. Every car registered in the UK must have a catalytic converter fitted by law. It became standard for petrol vehicles in 1992, and 2001 for diesel cars.A typical catalytic converter is made of ceramic blocks with a porous structure. By coating the pores with a selection of valuable metals: platinum, rhodium and palladium, they act as a filter to break down the toxic exhaust gases produced by burning petrol.The metal coatings work far better as filters when they’re heated, so their position next to the engine offers the ideal environment for just that. The converter can then perform the chemical reaction required to break down the poisonous gasses into less harmful products with much greater ease.

Question 2

How often should a catalytic converter need replacing?

Accepted Answer

A catalytic converter will usually need to be replaced after 70,000-100,000 miles, or if you begin to experience any of the above symptoms. Regular maintenance and checks (including an MOT) will determine whether you need to replace your converter or if it’s good to go for a few more miles.How you drive, and the typical usage of your car, will affect its lifespan too. Your converter could wear out quicker if your car is predominantly used for short journeys in stop/start traffic. Your converter works better at a required temperature, so if it’s not getting the chance to heat up properly, it isn’t going to be as efficient. This could shorten its effective life.

Question 3

The law, vehicle regulations and your MOT

Accepted Answer

Your vehicle’s emissions will be measured during your MOT test. If your car is found to break the legal limits, then that’s an immediate fail.In 2020, almost 1.3 million vehicles failed their MOT test last year due to dangerously high emissions. If you’re trying to keep your motoring costs down, then MOT retests are easily avoidable with regular checks and good car maintenance.

Question 4

What happens during a catalytic converter replacement?

Accepted Answer

Our certified mechanics will:
Raise your car completely off the ground, making sure that the exhaust has had time to cool down before they begin the replacement.
Locate the catalytic converter. It usually looks like a box in the middle of the exhaust system underneath the car.
Remove the catalytic converter, inspect it and fit a replacement if necessary
Test the new catalytic converter, taking care to double check that the replacement catalytic converter is up to the correct specifications for the vehicle’s emissions standards.

Question 5

What causes a catalytic converter to break?

Accepted Answer

Most catalytic converters will last the lifetime of a vehicle. But in some cases, a converter will go bad and need to be replaced. Almost all problems with a catalytic converter are due to an engine issue. It is usually caused by excess fuel entering the exhaust system due to an incorrect air/fuel mixture, failing spark plugs, incorrect engine timing, a faulty oxygen sensor, or other issues where fuel leaves the engine’s combustion chamber unburned.When this happens, the catalytic converter gets too hot and begins to melt, causing significant performance problems. Without proper maintenance, carbon deposits can also clog the catalytic converter, or worst case, block it completely.

Question 6

When should a catalytic converter be replaced?

Accepted Answer

The expected lifespan of a catalytic converter is usually between 70,000 and 100,000 miles. Regular maintenance and checks (including an MOT) will determine whether you need to replace your converter or if it’s good to go for a few more miles.How you drive, and the typical usage of your car, will affect its lifespan too. Your converter could wear out quicker if your car is predominantly used for short journeys in stop/start traffic. Your converter works better at a required temperature, so if it’s not getting the chance to heat up properly, it isn’t going to be as efficient. This could shorten its effective life.

Question 7

What are the symptoms of a bad catalytic converter?

Accepted Answer

Usually, there a few signs you can look for:
Significantly reduced engine performance.
Dark smoke is coming from the exhaust.
Poor fuel efficiency.
If you experience issues while accelerating.
If you can smell sulfur (rotten eggs) coming from your car.
When the ‘check engine’ warning light illuminates.

Question 8

How often should you replace your catalytic converter?

Accepted Answer

A catalytic converter will usually need to be replaced after 70,000-100,000 miles, or if you begin to experience any of the above symptoms. Regular maintenance and checks (including an MOT) will determine whether you need to replace your converter or if it’s good to go for a few more miles.How you drive, and the typical usage of your car, will affect its lifespan too. Your converter could wear out quicker if your car is predominantly used for short journeys in stop/start traffic. Your converter works better at a required temperature, so if it’s not getting the chance to heat up properly, it isn’t going to be as efficient. This could shorten its effective life.

Question 9

What happens during a catalytic converter replacement?

Accepted Answer

Our certified mechanics will:
Raise your car completely off the ground, making sure that the exhaust has had time to cool down before they begin the replacement.
Locate the catalytic converter. It usually looks like a box in the middle of the exhaust system underneath the car.
Remove the catalytic converter, inspect it and fit a replacement if necessary
Test the new catalytic converter, taking care to double check that the replacement catalytic converter is up to the correct specifications for the vehicle’s emissions standards.

Question 10

What is the average life of a catalytic converter?

Accepted Answer

This can vary from car to car and from driver to driver, however the estimated lifespan of a catalytic converter is between 70,000-100,000 miles, or if you begin to experience any of the symptoms previously mentioned.

Question 11

Can you drive with a broken or missing catalytic converter?

Accepted Answer

Your car will most likely still be drivable, however bad catalytic converters are terrible for the environment, and driving without one is even worse. A blocked or damaged converter can cause further damage to your car, resulting in a more expensive repair in the long run.There are strict regulations and laws around vehicle emissions, therefore if you get caught by the police with a broken or missing catalytic converter you may be fined.

Question 12

What happens if you don't change a broken catalytic converter?

Accepted Answer

Failing to replace a catalytic converter can result in more damage to your car, poor fuel efficiency and a potential fine from the police. If the converter has begun to function poorly due to it being clogged up, it will cause the vehicle to run extremely poorly.

Question 13

BMW

Accepted Answer

BMW AG is a German automobile and motorcycle manufacturer that was established over 100 years ago in March 1916. They also own Mini and Rolls Royce, after taking over the two British marques in 2000 and 1998 respectively.

Question 14

How popular is BMW in the United Kingdom?

Accepted Answer

BMW makes luxury vehicles and is possibly most famous for its sports saloon models. In 2018, BMW had 1.9m vehicles on the roads in the UK, a number that has been steadily increasing each year for the past decade.As one of the ‘big 3’ German marques, along with Audi and Mercedes, BMW carries a strong reputation for making high-quality stylish vehicles, and have captured a large section of the UK market.

Question 15

Luxury family and business models for every driver

Accepted Answer

Probably most popular for the 3 Series and 5 Series saloon models, BMW has got every possible angle covered for the more discerning drivers.The full range includes everything from the 1 Series city car to the full-size saloons and sports coupes of the 7 and 8 Series models.To provide everything you’d ever need for family motoring there’s a seven-seat MPV, their range of X model SUVs, and since 2014, the introduction of their plug-in electric i models. Top it all off with their M model high-performance supercars, the Z4 convertible and the i8 Roadster—and you’ve got the full package.

Question 16

BMW: High performance on and off the track

Accepted Answer

BMW has a successful history in a range of motorsports.They have been significant performers in touring car racing and rally driving, enjoyed success in Formula One with the BMW Sauber team, and BMW cars have been regular competitors and winners at Le Mans since the race’s early years.

Question 17

BMW’s reliability and reputation

Accepted Answer

BMW ranked 16th place out of 30 car brands in the What Car? Reliability Survey in 2018. BMW hasn’t always had the best reputation for reliability but to rank alongside marques such as Honda, Volkswagen and Fiat they’re holding their own alongside plenty of the other big names.

Question 18

Recent BMW recalls and reliability issues

Accepted Answer

Various recalls have been made on BMW models throughout their motoring history. The following are a list of the most recent in the UK and Europe.

Question 19

22/03/2019 – BMW X5 (2018)

Accepted Answer

Incorrect tightening torque of left front seat fixing bolts

Question 20

22/03/2019 – BMW X5, 5 Series (2000–2003)

Accepted Answer

Potential rupture of driver front airbag inflator

Question 21

04/03/2019 – BMW X1 (2018–2019)

Accepted Answer

Rear lights may be fixed with incorrect securing units

Question 22

01/03/2019 – BMW X5, X6, 7 Series, 6 Series and 5 Series (2009–2011)

Accepted Answer

Auxiliary water pump’s electronics could lead to a short circuit

Question 23

01/02/2019 – BMW X5 and X6 (2007–2010)

Accepted Answer

The idler pulley bolt could become loosened

Question 24

21/01/2019 – BMW M3, M4 and M4 convertible (2016)

Accepted Answer

The flange of the propshaft may become detached

Question 25

27/12/2018 – BMW X6 (2014–2015)

Accepted Answer

EGR module cooler could leak

Question 26

27/12/2018 – BMW 4 Series (2013–2015)

Accepted Answer

Exhaust gas recirculation module cooler could leakAll recall information sourced from gov.co.uk data.

Car make and model	Average dealer price	Price estimate	Average savings
BMW Z4	£505	£364 - £445	£101
BMW 2 Series Coupe	£572	£417 - £510	£108
BMW 3 Series Gran Turismo	£391	£299 - £365	£59
BMW 6 Series Gran Turismo	£505	£379 - £463	£84
BMW 5 Series Gran Turismo	£480	£369 - £451	£70
BMW Z4	£478	£366 - £448	£71
BMW i8	£543	£414 - £506	£83
BMW 6 Series	£451	£369 - £451	£41
BMW 7 Series	£504	£363 - £444	£101
BMW X1	£466	£378 - £462	£46
BMW X3	£399	£298 - £365	£68
BMW i3	£612	£436 - £556	£116
BMW X4	£462	£340 - £415	£84
BMW 4 Series Cabriolet	£398	£286 - £350	£80
BMW 2 Series Coupe	£572	£417 - £510	£108
BMW X2	£383	£311 - £380	£38
BMW 2 Series Gran Tourer	£383	£311 - £380	£38
BMW 6 Series Gran Turismo	£505	£379 - £463	£84
BMW X6	£451	£369 - £451	£41
BMW i8	£543	£414 - £506	£83
BMW Z4	£505	£364 - £445	£101
BMW 2 Series Coupe	£572	£417 - £510	£108
BMW 3 Series Gran Turismo	£391	£299 - £365	£59
BMW 6 Series Gran Turismo	£505	£379 - £463	£84
BMW 5 Series Gran Turismo	£480	£369 - £451	£70

BMW catalytic converter replacement

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Our expert insights into BMW catalytic converter replacement

Our expert insights into BMW catalytic converter replacement

What does a catalytic converter do?

What are the symptoms of a failing catalytic converter?

What happens during a catalytic converter replacement?

How much does it cost to fix my car?

What does a catalytic converter do?

What are the symptoms of a failing catalytic converter?

What happens during a catalytic converter replacement?

How much does it cost to fix my car?

Our trusted and certified garages

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London, UK

Holocene Motor Group

London, UK

Blenheim Transport Ltd

London, UK

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London, UK

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London, UK

Universal Automobile Engineers

London, UK

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