Possible Causes of EVAP Leaks
Evaporative emission system leaks can be caused by a few different underlying issues, some of which can be relatively difficult to identify. Being aware of the possible causes will aid in a timely diagnosis.
1) Loose/Broken Fuel Cap
The most common cause of EVAP leak-related failures is a loose or broken gas cap. It’s even possible for the fuel cap to be completely missing. Don’t worry if you accidentally left your cap at the gas station. Countless others have done the same thing.
Fortunately, this problem can be easily and relatively inexpensively fixed with a quick trip to just about any local auto parts store (or by ordering online).
Most replacement gas caps are available for under $30 and are usually very easy to install. It’s best to assume that the gas cap is the culprit until you can rule it out.
2) Damaged EVAP Components
Another possible cause of EVAP system leaks is deterioration of key system components due to aging or impact. The most commonly affected components in the EVAP system include the charcoal canister, EVAP purge solenoid valve, purge valve, and vent valve. In fact, even a damaged fuel tank can cause EVAP system leaks.
3) Poor Connections/Damaged Cables
EVAP systems are also commonly affected by electrical distribution lines that are worn out or have pinhole leaks. These lines are used throughout the EVAP system to redirect captured fuel vapors as needed.
Additionally, leaks can also occur at various connection points between these lines. Is it safe to drive with an EVAP leak? Yes, it is safe to drive a vehicle that has one or more leaks in the EVAP system. The chances of any damage to your vehicle’s components in the short term are very low. So, it’s not the end of the world if you don’t replace your gas cap or make an immediate trip to a repair shop. However, that doesn’t mean you shouldn’t take an EVAP leak seriously.
On the contrary, this type of leak can lead to a reduction in overall engine power and even increased fuel consumption for affected vehicles. However, affected vehicles should be able to drive normally.
In rare cases, the vehicle may have trouble starting. If this is the case, do not use the affected vehicle until the appropriate repairs have been made (you don’t want to be stranded somewhere).
Also note that the presence of one or more leaks in the EVAP system may cause your vehicle to fail mandatory emissions testing if one is required.
In any case, the root cause of the leak in your vehicle’s EVAP system should be thoroughly diagnosed and addressed as soon as possible. This will help you save fuel in the long run while ensuring that your vehicle’s engine continues to run as efficiently as possible.
How EVAP leaks affect the environment
As most people know, a vehicle’s evaporative emissions device is part of the exhaust system of a modern car. All devices of this type are designed to reduce the environmental impact of using an internal combustion engine. Other exhaust-related components found in modern vehicles include catalytic converters, EGR valves, and O2 sensors.
These raw fuel vapors can contribute to the formation of ground-level ozone, the main component of smog. Ozone can irritate the airways, aggravate asthma, and damage the lungs. Additionally, some of the hydrocarbons contained in fuel fumes are toxic and potentially carcinogenic.