Reasons why your vehicle Failed its Emissions Test

 
While failing an emissions test can be annoying enough for a car owner, not knowing the reason why it failed can make it even more frustrating. However, learning the common reasons why your vehicle has failed an emissions test can help you to fix the problem quickly and/or help prevent you failing one in the future.
 
A rich fuel mixture is one of the most common reasons for failing an emissions test. The high fuel/air mixture can be caused by a leaky injector, high fuel pressure or an oxygen sensor that has been contaminated. In fact, a faulty oxygen sensor can not only mess up your fuel/air mixture, but it can also cause overheating in your vehicle and cause it to lose power.
 
Both the ignition system and the air injection system are used to limit the amount of hydrocarbons emitted. If either system is not working properly, your vehicle will be giving off high amounts of toxic gases. One of the biggest causes for system failure are worn out or damaged spark plugs.
 
Finally, a leak can easily cause you to fail an emissions test. Some of the most common leaks are vacuum leaks and leaky fuel injectors. If you can find the source of the leak, you should have it fixed right away so you can pass your vehicle’s emissions test.
 
Patrick Britton