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Lexus ES300 Catalytic Converter

Major Problems Told By a Bad Lexus ES300 Catalytic Converter

So your Lexus ES300 had the engine light on, and you used a scanner to figure out the problem. Results showed P0420 and/or P0430: bad catalytic converter/s. But the part isn't supposed to fail by itself. Problems are often a result of issues outside the operating capacity of a converter. A malfunctioning unit is a symptom of deeper and more alarming engine and exhaust problems you should take care of immediately. Simply installing a new catalytic converter would only serve as a temporary repair. Here are a few examples of the common problems experienced by aging units and their underlying causes.

Rotten-egg smell

The easiest way to tell if something's wrong with your Lexus ES300 catalytic converter is when you begin to notice a foul, rotten-egg smell. This is a sign of a converter operating too hot. Check the temperature of the converter's inlet and outlet to verify the diagnosis. This is a result of the engine working with too much fuel during combustion. There may also be an ignition misfire, compression leak, leaky valves, and others. The unburned fuel goes to and gets processed inside the catalytic converter to produce the bad smell.

Poor performance and fuel efficiency

The following are some signs of a Lexus ES300 poorly running: stutters, slow acceleration, jerks, low power, and stalls. You may also notice a drop in fuel efficiency. If these are experienced, you may have a plugged converter caused by excessive backpressure. It's also possible that other parts of the exhaust-headers, mufflers, pipes-are the ones plugged. To be sure that the converter is the one causing problems, remove it from the system and try to pass a beam of light through it. If the light's not visible, then it's plugged. Work on the other components as well to solve the problem.

Colored exhaust

You may see that the exhaust fumes coming out of the tailpipe is colored black or blue. Just like liquid fuel in the converter, this is caused by an engine that's already burning engine oil during combustion. There are leaks that allow the oil to enter the combustion chamber. This new mixture results to a new kind of exhaust fume that is not designed to pass through the converter. To combat this, not only should the converter be worked on, but valves and rings in the engine should be replaced as well.

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  • Prolonging the Life of Lexus ES300 Catalytic Converters 04 March 2014

    The catalytic converters of a Lexus ES300 are among the most tireless components in a car. Despite their high and unforgiving work rate, it's very surprising that these don't require any maintenance at all compared to other parts. There really isn't any way to work directly on the converters-unless it's time to replace them. Here are good and easy practices to help you prolong the life of these expensive Lexus ES300 Catalytic Converters.

    • Use the right fuel.
    • The fuel used has a very big influence on how long the converters last: making sure you pouring in unleaded in a gasoline engine and what octane rating the fuel should be. Avoid using fuel additives as well unless it is allowed or specified for the ES300. As much as possible, avoid giving your engine a bad mixture to use during combustion. Don't let yourself accidentally pour in the wrong kind in your car. This is bad not only because it damages the catalytic converter, it can also damage the engine.
    • Check spark plugs and wires.
    • Fuel concerns don't stop with the fuel used. It's also important that the fuel is burned to prevent other symptoms of a bad catalytic converter. For the right amount of fuel to be burned inside the combustion chamber, make sure that the spark plugs and each of their wires are in good condition. Excess fuel not burned results to both loss in engine power and an overheated catalytic converter.
    • Keep valves and seals in good condition.
    • There are plenty of different valves and seals in the engine that are designed to contain substances in their proper place. Other than fuel, liquids that can also damage the catalytic converter are oil and antifreeze. If these somehow pass through their seals and make their way to the combustion chamber, expect clogs, poor exhaust flow, and damaged converters.
    • Avoid deep flood and snow.
    • It is never a good idea to drive your Lexus ES300 through deep flood or snow. Catalytic converters are designed to operate under a high, but tolerable, temperature. The very cold water or snow immediately has negative effects on the converter's performance.