The EVAP is perhaps the most underrated part of any vehicle… Many think of it as just a trivial emissions control device that has no role whatsoever in the vehicle’s overall performance―which, by the way, is far from the truth. The evaporative emission control system does much more than simply capture hydrocarbon vapors from the fuel tank. It enables the engine to burn fuel the most efficient manner possible. If it leaks, it will impact the way your vehicle operates.
EVAP System in A Nutshell
Did you know…
As per a report published by the National Emission Inventory, vehicles driven in the United States generated about 2.5 million tons of volatile organic compounds in 2014.
The sole purpose of incorporating EVAP systems into gasoline cars is to reduce the release of harmful fuel vapors into the atmosphere. The system essentially makes use of components like the charcoal canister and purge valve to capture volatile organic compounds evaporated from the the gas tank. The captured VOCs are then directed into the combustion chamber to be burned along with the air-fuel mixture.
If the system develops a leak, VOCs produced by the gas tank will be escaped into the atmosphere. Not only that… A defective EVAP, if not repaired or replaced in time, can contribute to all sorts of performance-related issues. The discussion below sheds light on some of the issues that you might have to deal with if your Audi Q7’s EVAP system acts up.
Immediate Consequences of An EVAP Leak
#1- Poor combustion… reduced fuel efficiency
Optimal pressure within the fuel lines is critical for a timely delivery of gasoline into the engine. If there is something off with your Audi Q7’s EVAP, pressure within its fuel delivery system will be impacted… This disruption can destabilize the air-to-fuel ratio inside the combustion chamber… which can cause the engine to burn fuel inefficiently.
#2- Performance related issues… like rough idling and stalling
This is yet another issue that you might have to deal with if your Audi Q7’s EVAP is not working the way it should… whether it’s because of a leak or any other reason. A defective EVAP can destabilize the air-to-fuel ratio within the cylinders. An imbalanced air-to-fuel ratio in the combustion chamber can cause the engine to run rich or lean, act erratically, idle roughly, and stall frequently.
#3- Increased emissions
You would be surprised to know that evaporative emissions (VOCs) account for around 8% of the total amount of pollutants from the vehicle… Unbelievable, right? Since the EVAP system is responsible for eliminating the most of those emissions, if it malfunctions… your Audi Q7’s compliance with emission regulations will be compromised. And yes… it might even fail the emissions test.
Long Term Impact
#1- Strain on the fuel delivery system
Nope… this is not a made-up point. A defective EVAP system can place extra strain on your Audi Q7’s fuel delivery system―impacting the functionality of its key components in the long run. You would be surprised to know that a defective EVAP system can cause key fuel delivery system components like the fuel pump, injectors, and pressure regulator to malfunction gradually.
#2- Potential for engine damage
If your Audi Q7 EVAP system is not functioning properly and you don’t address the issue, it could damage critical engine components like the spark plug, fuel injectors, valve train, etc. It may also contribute to expensive engine repairs in the long run… So, if you suspect a glitch in your vehicle’s EVAP, have it checked at the nearest service center. Consider replacing it if it has reached the end of its serviceable life.
#3- Decreased vehicle resale value
The resale value of your Audi Q7 will hit the rock bottom if you continue driving it with a defective EVAP system. If you want to preserve the performance characteristics of your beloved vehicle, pay special attention to its emissions control system components… particular the EVAP system.
Closing Remark
The EVAP system your Audi Q7 is outfitted with is much more than just an emissions control device. If it malfunctions or develops a leak, you may experience all sorts of drivability issues… ranging from sluggish acceleration to poor fuel efficiency. If left unattended, a leaky EVAP system can result in permanent engine damage…
