5 Reasons Your Car Will Likely Fail an Emissions Test

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5 Reasons Your Car Will Likely Fail an Emissions Test

McKonly's Garage Blog

Most vehicles need to go through emissions testing on a biannual basis in order to become legally licensed. If your car or truck has ever failed emissions testing you understand that it can be a quite stressful. After failing you will need to visit a mechanic that can conduct the necessary repairs that will allow you to register your vehicle. Fortunately some of the most common problems that cause an emissions test to be failed are relatively inexpensive to fix. These are five of the most common reasons a car will fail an emissions test.

Faulty O2 Sensor

An oxygen sensor that malfunctions will not be able to properly monitor exhaust fumes and this can result in additional issues for a vehicle that include a decrease in engine power or a rough idle, not to mention a drastic drop in fuel efficiency. The issue that concerns the testing facility is that a bad oxygen sensor will increase the toxicity of your vehicle's emissions.

Rich Fuel Mixture

If there are high amounts of carbon monoxide in your vehicle's emissions it is likely that there is excessive burning of gasoline occurring, which is called running rich. This may happen due to a faulty Mass Air Flow sensor or because of leaking, clogged or otherwise malfunction fuel injectors.

Incorrect Fuel Metering

Fuel usage is monitored to ensure that the proper amount of gasoline is being burned to create a smooth running engine If the engine control or fuel injection unit malfunctions the fuel monitoring will be incorrect, which can result in increased emissions and a failed test.

EVAP System

The Evaporative Emission Control System, or EVAP, prevents the release of gas fumes from the vehicle into the atmosphere. This system may malfunction if there is a leak in the vacuum hoses or vents or due to a broken, cracked or even just a loose gas cap.

Exhaust Leak

An exhaust leak can cause all sorts of problems for a vehicle and it is fairly obvious how this would result in a failed emissions test. Not only will an exhaust leak throw off the reading of the O2 sensor, it means the fumes may not be passing through the catalytic converter, which changes them to less harmful emissions.

If your vehicle is due for an emissions test or needs emissions repairs in Lancaster bring it to McKonly's Garage. We are a PA Safety & Emission Inspection station that conducts all necessary testing and repairs to keep your car legal! Give us a call at (717) 208-8210 to request an appointment today, and be sure to check out our special offers!

McKonly's Garage Blog

Written By Brian Corey

Published By MORBiZ