An EVAP leak occurs when the emission control system in a vehicle has been faulted.
This particular part of the vehicle keeps gas fumes confined to the gas tank. When there is a leak, these fumes get into the atmosphere and cause air pollution.
While it is technically safe to drive with an EVAP leak, there are certain things you should be aware. This is a major problem that needs to be addressed for a number of reasons.
Causes of EVAP Leak
One potential cause of an EVAP leak is when the hoses that transport gas fumes to the engine gets damaged. While these hoses are usually pretty durable, they can wear away over time. Regular wear leads to a leak if the damage is not repaired or replacements aren’t done.
This type of leak can also happen when the charcoal canister wears away or is damaged from blunt force. Vapor can rise up through even very small cracks. If the canister has any cracks in it, you will have to pay for a full replacement.
In somewhat rare cases, a malfunctioning purge valve or vent control valve can be to blame. If one of these valves becomes stuck for any reason, they cannot do what they are designed to properly. This can result in gas vapor leakage, but it doesn’t happen very often.
Believe it or not, a simple loose cap on the fuel tank is usually the reason for an EVAP leak. Whether the cap is broken or you didn’t put it back on properly, this is something you should check before going anything else.
Signs Your Vehicle May Have an EVAP Leak
First you will need to be aware of the signs of an EVAP leak so you can spot the problem quickly.
1. Check Engine Light
One of the first signs of an EVAP leak is the check engine light on the dashboard coming lighting up. There can be many reasons for this, but it is a common symptom that you should pay attention to. It is important to get your vehicle looked at any time you see this light come on. Make sure that the cap on the fuel tank is put on all the way. If the cap is loose at all, you could get a check engine notification on the dash.
2. Fuel Odor
Some vehicles that have this type of leak will produce a distinct fuel odor. This all depends on the kind of car you drive, but it is something to look out for. It is more common with older vehicles, but it’s still possible with newer models.
3. Lower Gas Mileage
If your vehicle doesn’t seem to be getting the gas mileage it used to, you might have an EVAP leak. The mileage of a car tends to decline slowly over time, but it is much more rapid with this type of problem. This is something that you should notice fairly quickly.
4. Odd Sounds
You might notice a strange popping or clicking sound coming from your vehicle if you have an EVAP leak. This happens when the 3 or 2-way EVAP valve is unable to function properly. It keeps attempting to pressure the fuel tank, which is what leads to these clicking sounds from the magnet valve. It might be faint at first, but it will likely get faster clicking the longer you go without addressing the problem.
Why You Shouldn’t Drive with an EVAP Leak
While it isn’t dangerous to drive around with an EVAP leak, there are a couple of good reasons to avoid doing so.
The first reason is that you will be harming the environment. Your car is leaking gas fumes, which contributes to the destruction of the ozone layer.
If you live in a state that requires emission tests, you are going to fail unless you fix the leak. This can result in anything from a fine to simply not being able to renew your vehicle’s registration. An EVAP leak will prevent you from passing this test.
Diagnosing an EVAP Leak
There are ways of diagnosing an EVAP leak without taking your vehicle to a mechanic. The first and simplest way is to simply check your gas cap. If the cap is not fully tightened, all you have to do is put it on properly. This could clear up the problem immediately.
If the fuel cap is not the issue, you can use a scan tool. These tools can be fairly expensive, but it is well worth the expense. You can use this type of device to check for certain errors that are associated with specific problems.
For example, a “P0440” code means that you have a malfunctioning evaporative emission control system. There is also the “P0442” code, which indicates a leak in your EVAP system. If you want to save yourself some time and inconvenience, this tool can be very useful.
Cost of Fixing an EVAP Leak
The cost of having an EVAP leak fixed can range from around $100 to over $500. This largely depends on the cause of the leak and where you go to have the work done. Some causes only require minor repair work, while others require replacement parts. The design of your vehicle is something else that will affect how much you pay.
If you have this type of leak due to any damaged parts, it is usually better to just have them replaced. Repair work is typically less costly, but the problem might occur again in the near future. You should listen to your mechanic’s recommendation before making a decision. Spending more in the short term can save you money later on.
Some people put off getting their EVAP leak fixed because it isn’t necessarily dangerous, but it’s still something you should get fixed as soon as possible. The leakage of gas fumes from your vehicle is bad for the environment and could result in having to pay fines.