With air quality getting worse quickly, governments have put strict rules in place to limit the amount of pollution in the environment, most of which comes from cars. To help cut down on the number of toxic fumes that cars emit, car manufacturers put a catalytic converter in the exhaust system of their cars. Do diesels have catalytic converters? A lot of people who drive diesel cars want to know if diesel cars have an emissions system and how it works.
The quick answer is that diesel cars that were produced before 1990 do have catalytic converters but they are different from the ones that work in gas engines.
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Do Diesels Have Catalytic Converters?
Old engines don’t have this technology, especially if they were made before 1990. There were some technological changes made before this point, though, to help cut down on emissions. Newer engines that are made for the European market all have catalytic converters in them. As technology gets better and more progress is being made in this area, it’s not clear if there are more ways to cut down on emissions.
How Does a Diesel Catalytic Converter Work?
The catalytic converter is very important because it converts harmful compounds into non-harmful ones. The inside of its metal casing is made up of two ceramic boxes with thousands of micro-cellular modules that look like honeycombs.
Metals like platinum and palladium are put on the ceramic blocks. This makes them more durable. This is because it is close to the engine, the catalytic converter usually gets hot up and starts chemical reactions that turn toxic gases into harmless byproducts before they are emitted into the air.
The Diesel Oxidation Catalyst (DOC) works almost the same way as a petrol engine. They use metal catalysts to help make water and carbon out of carbon monoxide. Because they do this, they don’t let harmful gases like hydrocarbons and volatile byproducts get out into the air, making them less harmful.
However, unlike petrol-based catalytic converters, diesel-based catalytic converters don’t have rhodium.
SCR, also known as DEF, is a type of catalyst that helps break down Oxides of Nitrogen (NOx) from cars and turn them into Oxygen and Nitrogen. It uses an ammonia-based catalyst to do this. There is a chemical reaction that takes place when the reductant and exhaust go over the SCR catalyst. It turns NOx emissions into water and nitrogen gas.
About 75% to 90% of the time, the open-loop SCR system is good at reducing NOx emissions. There are stationary engines with systems that can work more than 95% of the time, though. SCR also cuts hydrocarbon emissions by about 8%. It can run better if it runs on fuel that has a lot less sulfur in it.
How Long Do Diesel Catalytic Converters Last?
It usually lasts for 10 years or 100 000 miles. The length and number of stops the car makes will also play a role in how long and how many times it stops. The catalytic converter will wear out more quickly in a car that makes short start-stop trips than in one that drives long distances all the time.
Since the engine is managed to turn off before the catalytic converter achieves its ideal temperature range, it doesn’t do its job well. Even though catalytic converters can last for a long time, they must be checked on a regular basis for both external and internal impairment. It costs a lot to replace one that has been damaged.
How Do You Know If You’ve Got A Bad Car Converter?
If you drive your car long enough, it’s possible that your catalytic converter will break down. This can happen for many reasons, such as when carbon deposits build up. This can slow down the flow of exhaust gas. Overheating, physical damage, and contamination could also be the cause.
Some of the signs of a bad catalytic converter are:
- Decrease in speed
- Slow performance of the engine
- Dark smoke comes out of the car’s tailpipe.
- Something from the exhaust that smells like rotten eggs or sulfur
- There is too much heat under the car.
A modern car has a sensor that lights up red if the converter isn’t working right. If you see any of these signs, you should get your car checked out right away.
Catalytic converters play an important role in cars because they stop harmful gases from being released into the air. It’s not just the catalytic converter that cleans the car’s exhaust. Most cars today also have Ad Blue selective catalytic reduction technology, exhaust gas recirculation, and diesel gas particulate that help clean the exhaust fumes. However, it is important that you have the catalytic converter checked out on a regular basis to keep it at its best.
Hi there! I’m Naomi O’Colman. I’ve got years of experience working at an auto repair shop here in Texas under my belt. On top of that, ever since I was a kid I’ve been passionate about the auto industry. Since I’ve joined the team at automotivegearz.com I’ve been enthusiastically sharing my passion and insights with my readers. I’m dedicated to delivering high quality content and helping you stay up to date with the latest automotive trends and products out there!