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BMW 318i Catalytic Converter

Cat Catastrophe: Troubleshooting Your BMW 318i Catalytic Converter

If you treat your BMW 318i as a friend, Mother Nature treats it as her enemy. Exhaust emissions from vehicles are among the leading causes of air pollution, and, truth be told, your BMW is a big, moving environmental hazard. Well, all vehicles are actually considered as pollutants, what with all the carbon dioxide and hydrocarbon emissions continuously streaming out of them. Fortunately, catalytic converters were invented to help protect the environment from the harmful effects of exhaust emissions. As a responsible driver, you need to do your part in protecting Mother Nature. One of the ways you can do this is by ensuring your BMW 318i catalytic converter is always in good condition. A properly working cat will help make your vehicle more eco-friendly, so you can feel less guilty about driving your vehicle daily. If your cat's malfunctioning, lethal exhaust emissions from your engine won't be converted into less harmful substances properly, resulting in acceleration problems, power loss, poor fuel economy, rough idling, and frequent stalling. Your converter doesn't have to reach the point of total failure, though, as long as you troubleshoot and try to fix the problems right away. We've listed a few tips to help you out.

The smell of rotten eggs

Surprisingly, the kitchen is not the only place where you can smell the stench of rotten eggs. This foul odor can also fill up your vehicle if you have a bad catalytic converter. Usually, a stinky vehicle has an overheated and malfunctioning converter that emits a smell similar to that of rotten eggs. This is usually caused by improper fuel mixture and extreme temperature in the converter's ceramic monolith. The incorrect fuel mixture also causes a spike in the amount of hydrogen sulfide in exhaust emissions, prompting the converter to produce a foul odor. If your vehicle reeks of this smell, have your converter checked immediately for possible damage.

Odd rattling noise

Aside from emitting a foul smell, a bad catalytic converter will also produce an odd rattling noise. Thermal shock is usually the culprit behind this problem, as converters are not designed to handle extreme temperature change. Sudden shifts in temperature can cause the converter's housing to contract and crush the internal ceramic substrate, creating highly audible rattling noises. To check for ceramic substrate damage, lightly tap the outside of the converter with a rubber mallet. If the converter gives off a rattling noise while you're tapping, then it means the ceramic substrate is broken. Take the converter to a mechanic or have it replaced as soon as possible.

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  • Cat Care: Tips in Maintaining Your BMW 318i Catalytic Converter 27 February 2013

    Vehicles are probably one of the most remarkable inventions in history, but their birth also paved the way for increased air pollution and environmental damage. The combined exhaust emissions from vehicles turned previously clean cities into areas filled with air pollution, and it wasn't until the mid-70s that another great invention was developed and introduced to vehicle owners. This device, called as the catalytic converter, magically turns noxious exhaust emissions into less lethal substances that can deal little to no harm to the environment. But no matter how great this invention is, it is still vulnerable to damage and failure, especially after many years of use. Your BMW 318i catalytic converter is not an exception. Even with its durable construction, your converter may also break down over time, causing poor vehicle performance, acceleration problems, frequent stalling, poor fuel economy, and increased engine temperature. You can prevent these problems from happening, though, by practicing regular maintenance on the converter. This is basically the key to prolonging the converter's life and keeping it in tiptop working condition. Here are a few tips you can follow to maintain your converter:


    Clean the converter.


    Catalytic converter maintenance starts with proper cleaning. Over time, the carbon and debris may build up in the converter, causing it to perform poorly. Using the wrong fuel may also cause mild oil fouling and residue buildup in the converter. Fortunately, you don't have to replace your converter right away when these problems happen. To get rid of the deposits and carbon buildup, use a catalytic converter cleaner or deodorizer. Simply pour the contents of the cleaner to your gas tank, and you're good to go. The cleaner will work its magic to your converter and engine as you drive, leaving you with a more efficient cat even before you reach your destination. Aside from eliminating deposits, the cleaner can also improve your fuel efficiency and prolong your converter's life. For best results, clean the converter every 6,000 miles or at least twice a year.


    Avoid areas with heavy snow.


    Extreme temperature change can deal severe damage to a heated converter. As much as possible, avoid driving through areas with heavy snow to protect the converter from cold elements. Sudden shifts in temperature can crack and even break the internal ceramic substrate of the converter, leaving you with no choice but to get a replacement. Try to avoid these areas if you can.