Is it OK to drive with an EVAP Leak, you ask?
You may know you have a leak or suspect you have a leak but when it comes to whether it is ok to drive with an EVAP leak, the answer is simple but contains a both environmental and ethical considerations.
Lucky for you, we have broken this question down into easily digestible chunks.
This article will answer your question (without beating around the bush) but it will also go a bit deeper into what the EVAP system actually is, what causes leaks, symptoms of an EVAP leak and more so please read on.
But for the quick answer, read the paragraph below:
Is it Ok to Drive with EVAP Leak
An EVAP system ensures that gasoline vapors do not escape from your vehicle’s fuel tank into the atmosphere.
Therefore, without getting into any of the nitty gritty, it is technically “okay” to drive with an EVAP leak. Although, in doing so, you will be producing more harmful emissions and wasting fuel.
So, a mechanical standpoint, your car will still drive but from an ethical and environmental standpoint…
not so much!
All of us need to do our part to ensure that we can live in cities without excessive smog. Allowing your vehicle to leak from this system contributes to this smog and is detrimental to the environment. No only that, it can cost you a lot of money in wasted fuel.
If you do not want to spend more money on gasoline, you need to repair the system if it is damaged.
A mechanic can easily diagnose if you are having an issue with this by using the OBD II port on your vehicle. These ports were implemented as a standard feature on all vehicles made after the year 1996; depending on what kind of damage, you may be presented with a few different types of codes.
Each code will tell you what kind of damage has explicitly been detected by the vehicle’s systems so that you can . You must get these repaired if you discover an issue with your vehicle’s EVAP system.
So now, that you have the short answer, let’s go a bit deeper into what you need to know when asking, is It OK to Drive with an EVAP Leak.
What is the EVAP System?
EVAP stand for Evaporative Emission Control System (check out what it looks like here). They have been mandated by the Environmental Protection Agency to reduce the number of hydrocarbons released into the atmosphere when people drive.
To put it simply, An EVAP System helps to prevent your vehicle from constantly leaking fuel emissions into the atmosphere. When your EVAP system functions properly, it prevents these kind of leaks.
It does this by maintaining an airtight seal around your fuel tank and the fuel lines.
Components of the EVAP System
It is a ‘system’ and is therefore, composed of several different parts which can be found at several different locations. These components include:
- Fuel tank
- Gas cap
- Liquid-vapor separator
- EVAP canister
The fuel tank of your vehicle as part of its evaporative emission control system. Modern vehicles are created with extra space near the top of the fuel tank. So, the fuel in your vehicle can expand some when the temperature outside rises.
The gas cap of your fuel tank is also part of the vehicle’s evaporative emission control system. Vehicles that were created before the year 1996 use gas caps that have vents. Vehicles that were created after that year have gas caps that are sealed completely.
The liquid-vapor separator is situated on top of your vehicle’s fuel tank. It is designed to help prevent liquid gasoline from entering the vent line of the EVAP canister.
This is important because if liquid gasoline were to enter the vent lines, then there would be no room for the vapors from your fuel.
The EVAP canister is the final component of your vehicle’s vapor control system. You can typically find it in the corner of your engine bay or behind the rear quarter panel. It is filled with activated charcoal.
The activated charcoal acts like a vacuum and sucks up all fuel vapors for safe storage. These components rarely fail because the carbon should last for the entire lifespan of your vehicle.
What is an EVAP Leak?
Many components of gasoline can evaporate at low temperatures. This means that if there is a leak in your vehicle system, it could release many chemical vapors into the atmosphere. This will cause pollution that leads to smog (even when it is not being driven).
If any part of the EVAP systems gets damaged or comes loose, it can cause a leak.
The best way for you to diagnose whether your vehicle has one of these leaks is to use the OBD II port and scan it for codes.
The following codes are used when your vehicle leaks into its EVAP system.
- P0440: Evaporative Emission Control System Fault
- P0441: EVAP System Incorrect Purge Flow
- P0442: EVAP Small Leak Detected
- P0443: EVAP Purge Control Valve Circuit
- P0444: EVAP Purge Control Valve Circuit Open
- P0445: EVAP Purge Control Valve Circuit Shorted
- P0446: EVAP System Vent Control Circuit
- P0447: EVAP Vent Control Circuit Open
- P0448: EVAP System Vent Control Circuit Shorted
- P0449: EVAP System Vent Valve/Solenoid Circuit
- P0450: Evaporative System Pressure Sensor
- P0451: EVAP System Pressure Sensor
- P0452: EVAP System Pressure Sensor Low Input
- P0453: EVAP System Pressure Sensor High input
- P0454: EVAP System Pressure Sensor Intermittent
- P0455: EVAP System Leak Detected (gross leak)
- P0456: EVAP System Leak Detected (small leak)
- P0457: EVAP System Leak Detected (fuel cap)
Depending on the code that you received, the severity of the damage to your vehicle can vary. The more severe the damage is, the more quickly you need to have it repaired.
What Can Cause an EVAP Leak?
Many different things can cause a leak to develop in this part of your vehicle. The most common thing that will notify you of a leak in this part of your vehicle will be your vehicle’s check engine light.
The most common cause of your vehicle’s check engine light turning on when it relates to this part of your vehicle is the gas cap not being securely fit. This is very easy to correct is all you need to do is replace the gas cap and ensure that it is screwed on tightly.
A few other things can be a little more difficult to fix if you find that the gas cap is not broken. You could have holes in the fuel lines of your vehicle. There could be a leak in your vehicles EVAP canister. Basically, a hole in any part of the vehicles fuel system can cause a leak.
The best way to determine what is causing the leak is have it looked at by a mechanic. Depending on the codes that your vehicle shows, it could be very difficult for them to discover the underlying issue.
Symptoms of a Leak in your EVAP System
If you suspect that your vehicle has an issue with this part of its systems, you need to look out for a few common signs:
Smell of gasoline:
The most easily distinguishable sign will be the smell of gasoline. If you smell the strong and persistent gasoline vapors scent when you are in and around your vehicle, you need to have a mechanic check it out.
Decreased fuel Economy:
If you notice that suddenly the fuel economy of your vehicle seems to decrease quite a bit, then you also may need to go and have it looked at. You may also notice whenever your vehicle is idling that it seems to sputter a bit.
Decline in engine performance:
Finally, if you notice a sudden decline in your vehicle’s engine’s performance, then it could be from a leak in this part of its systems.
The difficult with diagnosing problems with your EVAP systems is that you may not notice anything at all. Servicing your car regularly should help with problems that would otherwise go undetected.
Is it Safe to Drive with an EVAP Leak?
Perhaps, you don’t want to know whether it is ok to drive with an EVAP leak but rather, is it safe…
Technically, it is safe to drive your vehicle if it leaks this part of its systems. Or at least, there is little risk of your car breaking down or in some way causing harm to your person.
That said, it certainly does not mean that you should drive with an EVAP leak.
If you were to drive your vehicle and leak in this system, you could contribute to pollution in your local area. Not only that, but even when your vehicle is turned off it will constantly leak vapors into the atmosphere.
If you care about protecting the environment (which you should), it in your best interest to discover any leak you may have in the EVAP system and get it taken care of immediately.
If you believe that you might have one of these leaks, the first thing you should do is go and check your vehicle’s gas. In the vast majority of cases, when someone has the check engine light in their vehicle turn on because of this system, the gas cap is not screwed on tightly enough.
Damages can occur to many parts of your vehicle’s fuel system and cause vapors to be emitted into the atmosphere. If you check out the gas cap and you do not discover anything, you should take it to the mechanic and have them take a look.
These systems can be difficult to diagnose even for trained technicians. They will help you determine the exact extent of the damages that your vehicle has suffered.
Cost of Fixing an EVAP Leak
Luckily, if there is an issue with this system in your vehicle, you wont have to absolutely break the bank with the repairs.
Typically, you can expect to pay between $200 and $500 or less to have this repaired. However, it can go above this if there is damage to the more costly components.
However, the price can vary depending on several different factors.
The amount you will be charged specifically will vary depending on your vehicle’s make and model, age, location, and mechanics. Depending on the extent of the damage and what all needs to be fixed, you could be charged different amounts.
If you just need to have the gas cap replaced, then you may only end up spending around $20.
Final summarising thoughts
The EVAP system in your vehicles is an essential part of its emission control system. So, when asking the question, is it okay to drive with and EVAP leak, the answer is two fold:
Yes, it is safe for you to drive with an EVAP leak but it is not safe for the environment. It not only contributes to pollution but the constant leak causes your fuel to deplete faster, costing you money.
The EVAP system helps to prevent gasoline vapors from leaking into the atmosphere and contributing to the formation of smog. Having a properly functioning EVAP system in your vehicle ensures that you are responsible for the environment when driving.
So, don’t let yourself become this person:
Vehicles that have leaks in these systems may see a decrease in the overall performance of their engine and you may need to fill up more frequently.
If you are experiencing the symptoms of an EVAP leak, it could be something as simple as the gas cap on your vehicle so check this first.
The best way for you to determine if your vehicle has an issue with this system is to use the OBD II port on it and read the codes. Although, in most cases out recommendation is to gett a mechanic to take a look.
That way, you can safely drive your car, free yourself of any worry about the direct negative impact your driving will have on the environment.
Do you know someone driving with an EVAP leak right now? Share this article with them to set the record straight!