Step by Step Guide on How to Bypass Evap Canister (Purge Control Valve)

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Is your car’s fuel vapor getting you chills? Struggling with a lousy Evap Canister and thinking to bypass the evap route? Take a moment holding your hood wrench as we’ll share a step by step guide explaining everything about bypassing Evap Canister.


What is Purge Control Valve or Evap Canister?

The best term to describe Evap Canister is the eco-friendly sidekick of your car. Evap canister is basically a charcoal-filled box that collects cloaked gasoline fumes from the fuel tank. This valve sucks and burns the entire vapor emerging as soon as the engine starts. And also turns the pollution into fuel efficiency.


In a nutshell – Bypass Evap Canister

Either near your car’s fuel tank or its engine bay, you’ll find an Evap Canister located there. Before you start the process to bypass the evap canister, make sure to detach the negative battery cable or terminal as well as the canister’s input/output lines. After that, install a line to bypass that would link the fuel tank with the intake system of the engine. Be sure about the connections to be secured using clamps. At last, rebuild the terminal connection for the negative battery.


What is the need of bypassing the Evap canister?

Although the Evap canister keeps the engine neat and clean, continuous processing makes the system heavy making it stuck for which this sidekick requires bypassing. Following mentioned a few reasons for bypassing the Evap Canister or purge control valve.

  • Purge control valve becomes faulty – As this valve manages the flow of vapor, damage might cause disruption with emission testing.  
  • Clogged nozzles – Collection of dirt and mud over the nozzles of canister often makes vapor flow clogged.
  • Damage in filter – To keep the gas free of sand or filter out all impurities from gas, filter plays the key part. This continuous process damages the filter and hence, requires bypassing the Evap Canister.
  • Exhausted charcoal – Charcoal is the prime feature of purge control, but it also loses its power of vapor-trapping when it gets damaged.


Step by step guide on how to bypass evap canister –

The whole process of bypassing the evap canister is like off-roading the ecosystem of your car. Therefore, we suggest you do it with caution. If you find the process messy or uncomfortable being greasy, then consult an automotive professional mechanic.

Required gears to equip with – Before you start the process, make sure to collect all the gears required to get this job done. Here’s the list of gears required –

  • Pliers
  • Wrench
  • WD-40
  • Caps and clamps for hoses

Steps to follow to bypass evap canister –

At times, you might need to temporarily bypass your EVAP canister. This step-by-step guide simplifies the process for you.

Step #1: Locate Your EVAP Canister 

Usually, Evap canister can be found near a vehicle’s engine compartment or fuel tank, but the specific spot can vary depending on the model of your vehicle. By properly referring to your vehicle’s manual or reading through any good online resources might help you reach accurate location details. To get an idea on where the Evap Canister is located, check this video out.

Step #2: Detach Negative Battery Terminal

To ensure safety in the whole process, we suggest detaching your vehicle’s negative battery terminal as it is the way to avoid electrical mishaps.

Step #3: Identify Canister’s Lines

Next step is to identify your Evap Canister’s input and output lines. So, the EVAP canister’s input line is attached from the fuel tank and output line is attached to the engine intake manifold. After having this clarity, you can proceed to the next step.

Step #4: Detach Input Line

Here, you need to be cautious of fuel pressure and very carefully use pliers to detach the input line of the canister. Also, make sure to have a container ready for any spilled fuel.

Step #5: Detach Output Line

With the help of an appropriate tool, you can detach the output line from the system, and here again you need to be cautious of fuel or vapors escaping.

Step #6: Install the Bypass Line

Now, you need to install a bypass line connected directly from the fuel tank to the engine intake by using a fuel-rated hose.

Step #7: Link with the Bypass Line

Here comes the time to link the first bypass line to the fuel tank’s input and the second to the engine intake while securing connections with hose clamps.

Step #8: Tighten all Loose Connections

After that, you need to conduct a thorough check to all the connections and tighten the loose ones to prevent fuel or vapor leaks.

Step #9: Reconnect the Terminal for Negative Battery

Once adequately secure, you should reconnect the negative terminal to restore power to your vehicle.

Step #10: System testing

This is also very important to be sure about your system’s functioning. For that, start the engine and observe it for unusual behaviors or leaks. Address any issues you notice on an immediate basis.

Step #11: Evaluating your Vehicle

Bypassing the EVAP canister might trigger some kinds of error codes or Check Engine indicators in the system of your vehicle. Monitor your vehicle for any such signs of trouble and also get it checked once from a good mechanic.

These steps provide insights into bypassing your EVAP canister. It covers reasons for bypassing, a step-by-step tutorial, and emphasizes consulting a professional mechanic for diagnosis and repair. Use this guide when facing EVAP canister issues.

That’s all you need to do to bypass the Evap Canister in your car. To avoid any unexpected event, a word of caution for you.

Related to emissions: Bypassing the Evap canister is basically giving the environment a thumbs-down. This step would more likely call up higher emissions, failed tests, and hefty fines. Therefore, be aware of it before you step ahead to bypass the evap canister.

Fuel System Woes: Bypassing can disrupt the delicate setting of your fuel ecosystem which would lead to performance issues and fuel problems later.


Final takeaway

Unless you’re so sure about fixing your car and its internal system, you should not consider involving yourself to fix your evap canister. It’s always a good idea to consult a mechanic who will diagnose the Evap issues and suggest the best repair plan. With a mechanic, you will be protected from environmental frowns and potential headaches.

So, remember, the Evap bypass is a last resort, not a joyride. Choose wisely, and keep your car and the planet happy!


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