4 Likely Reasons Your Car Will Fail an Emissions Test

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4 Likely Reasons Your Car Will Fail an Emissions Test

Nearly all vehicles must go through emissions testing on a regular basis in order to be legally licensed. If your car or truck has ever failed an emissions test you understand that it can be a stressful situation, requiring a trip to the mechanic to have the problem attempted to be repaired. But some of the most common issues that cause emissions test failure are generally less expensive than what you are required to spend "trying" to repair whatever issue is at hand. These are 4 of the most common reasons a vehicle will not pass an emissions test.

Failing EVAP System

The Evaporative Emission Control System, aka EVAP, prevents gasoline vapors from being released into the air. This system will not be able to function correctly if there is a leak in a connected vacuum hose or if there is a cracked, broken or loose gas cap.

Bad O2 Sensor

If your O2 sensor malfunctions it can not properly monitor exhaust fumes which may cause additional problems for your vehicle, including overheating, poor acceleration or a loss of engine power. However, the reasons this causes your vehicle to fail the test is that it can increase the hazardous fumes within your car's exhaust.

Rich Fuel Mixture

If high levels of carbon monoxide, which occurs if your vehicle is burning excessive amounts of gasoline, are detected in the emissions test your vehicle will not pass. This can happen due to a faulty O2 sensor or Mass Air Flow sensor or because of leaking fuel injectors.

Bad Fuel Metering

Your vehicle monitors fuel use to ensure that a correct air-fuel mixture is created to keep the engine running smooth. If the computerized engine control or computer aided fuel injection unit fails or malfunctions the monitoring will be incorrect, which will cause the vehicle to fail emissions.

If you need an emissions test in Valencia or if your vehicle has failed an emissions test in Valencia bring it to Simply Smog & Valencia Auto Performance at (661) 259-5600. Our team of certified technicians regularly conduct state inspections testing and repairs to the emissions system to ensure your vehicle can be legally licensed! Call us today or anytime you need auto repair in Valencia!

Simply Smog & Valencia Auto Performance Blog

Written By Brian Corey

Published By MORBiZ

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