5 Symptoms of an EVAP Leak
A common misconception in the world of automotive repair and maintenance is evaporative emissions. EVAP systems have been standard on all American vehicles for decades.
However, systems like these can sometimes develop leaks that need to be addressed. But how do you know if you have an EVAP leak? And what causes it? And most importantly, how much will it cost to repair?
What is an EVAP leak?
An evaporative emissions leak is essentially the incorrect release of fuel vapors into the atmosphere that occurs when a system designed to capture fuel vapors (the EVAP system) becomes damaged. This is perhaps best explained by first taking a closer look at the EVAP system itself.
Modern evaporative emissions systems are designed to capture fuel vapors as they leave the fuel system before they are eventually mixed with fresh air and reintroduced into the intake tract for combustion. The EVAP system itself consists of several main components, including the EVAP canister (charcoal canister), fuel tank, tank vent, and EVAP purge solenoid.
Essentially, an EVAP system leak can occur in any of these components or in the electrical distribution lines that run between them. If this occurs, raw fuel vapors can be released into the atmosphere, causing unnecessary pollution.
Common Signs of an EVAP Leak
Detecting an EVAP leak can be difficult, but there are several secondary symptoms that can help identify the problem, some of which are more obvious than others. Being able to recognize these symptoms is the first step to solving the problem as quickly as possible.
1) Check Engine Light
In most cases, an EVAP leak will cause the check engine light to be illuminated and at least one active diagnostic trouble code to be logged. The most common EVAP errors logged in this situation include P0440, P0442, P0455, P0456, and P0457.
2) Reduced Engine Power
Severe leaks in the EVAP system are known to cause a noticeable decrease in engine performance. This is because less fuel vapor is available for combustion. You may notice your car accelerating more slowly or not having the power it once had.
3) Reduced fuel consumption
In addition to the issues mentioned above, if your vehicle has an evaporative emissions problem, your fuel consumption will also decrease. This is also because not enough fuel vapors are available for combustion and are instead released into the atmosphere in such situations.
4) Starting issues
Another common symptom associated with an evaporative emissions leak is the affected vehicle’s difficulty starting or prolonged cranking. This type of problem occurs when the fuel-to-air ratio is unfavorably distorted, preventing efficient combustion.
5) Increased emissions
As you might imagine, a leaking EVAP system will also negatively affect your vehicle’s emissions. In these conditions, the vehicle’s exhaust tends to be too rich.