How to Test Purge Valve with Multimeter? Test a Car Purge Valve with Multimeter

how to test purge valve with multimeter

Multi-meter a small hand-held tool that is exclusively used to check for Voltage, Electric Current, and Resistance values. It’s also named as Volt-Ohm Meter in individual states around the globe. No matter your analytical needs, this little minion is one-man-army to check basic measurements or advanced calculations like battery voltage.

An electrician’s very first tool to check for any lagging point, disturbance, or issue is the multimeter. It can check for specific problems (electrical) on all kinds of engines, electrical appliances, power supplies, circuits, cables, and much more.

On the other hand, the Purge Valve is a small accessory used inside a car near the engine or sometimes near the fuel tank. This valve works by relieving fuel vapors that the charcoal has consumed as a result of combustion. Usually, when an engine’s control light fault seems to be undiagnostic, it’s due to a faulty yet unrecognized Purge Valve.

Simple Steps to Test a Purge Valve With Multimeter

As mentioned above, this little purge valve in a car or any other vehicle is an integral component of the Evaporative Emission Control (EVAP) system that controls fuel vapors’ emissions inside the vehicle and the environment.

To prevent any escapes, the purge valve traps them inside the charcoal canister and keeps reasonable control over the quantity of purged vapors coming from the canister.

The latest vehicles of today’s time feature an electronically connected and controlled system for this process. The simplest summary of the whole phenomenon is; the purge valve powers up the minute ignition starts, whereas the EVAP mechanism never operates if the engine isn’t working.

Furthermore, whenever you face any troubleshooting or technical problem in your car, you will need the best automotive multimeter.
Here are the 3 steps that you can use to check the functioning of the purge valve with a multimeter.

1). Locate the location: 

  • Before starting on, make sure that the engine is powered off at least 30 minutes before you start locating the position of the purge valve. Try to find the Purge Valve somewhere close to the machine or the fuel input.
  • It can also be found on top of the silencer or the sound muffler. You’ll see a charcoal canister here that would be residing the purge valve on the inside.
  • If you still feel it’s tough to find, try to read the manual, or you can also search online for the engine graphics of your specific vehicle to locate the purge valve.

2). Re-adjust the Cables:

  • Once you find the valve, you’ll notice that there’s a harness with 2 pins attached to the system.
  • Detach them from the system and reconnect with the multimeter cables of the testing kit.

3). Test the Valve:

  • Once you connect the cables with the multimeter, check for the resistance as it should be somewhere between 22.0ohms to 30.0ohms.
  • If the values seem to be any lower or higher than the stated values, you probably need to replace the valve to ensure standard functionality again.

Signs of a Compromised Purged Valve

If you are eager to know more about how to test the purge valve with a multimeter and fix it, you first need to be sure that the problem is due to the purge valve. Here are some signs that ensure the problem is with the valve;

  • Engine’s light goes off:

A car engine is involved in regulating the solenoid purge, and engine light lits if there’s anything wrong. The checking device usually shows Error P0446 or P0441 if purged vapor levels are altered.

  • The engine may have issues:

As mentioned above, the purged valve controls the outflow of fuel vapors into the environment. Contrarily, if the valve isn’t working, it will emit vapors in the atmosphere, which can adversely affect the air’s fuel ratio. In return, the engine would try to adjust accordingly, leading to rough idling or difficulty powering up.

  • Fuel’s Mileage may Decrease:

Poor functionality of a vehicle’s EVAP system will ultimately lead to decreased mileage. In addition, it will lead to the emission and accumulation of the fuel vapors into the atmosphere instead of the charcoal chamber, ultimately leading to high fuel combustion.

  • Failing at Emissions test:

As per the theory stated above, a low EVAP system and a compromised Purge Valve will result in excessive release of fuel fumes into the surroundings or the environment that will make the vehicle fail at the Emission tests.

  • Gaskets can be Ruined:

A malfunctioning EVAP system or the purge valve can lead to a disastrous accumulation of fumes inside the vehicle, and in extreme cases, it may blow up the seals and the gaskets. The corresponding consequences can be even more disastrous.

FREQUENTLY ASKED QUESTIONS

What to follow before testing a Car Purge Value?

The process is simple if done knowingly and confidently. Just find your car’s Purge valve’s exact location and disconnect its cables to connect them with the multimeter’s connection. Then, read the values to know if it’s working is fine or altered.

How do I know if a Purge Valve is bad?

Certain factors symbolize and show off if a purge valve isn’t working correctly. Some of these signs have been well-explained in the article above to help you understand your car’s situation.

How would you test an EVAP Valve?

To test an EVAP valve, you need to connect it to a vacuum. As you apply and hold the vacuum, you’ll notice that there isn’t any pressure, and that’s because it’s not having in the fumes anymore. The checker machine will show a p0441 Error that’s an indication of the poor purge valve.

Can a flawed Purge Valve ignite up a misfire?

It can! Poor working of the purge valve and the EVAP system can lead to the false and disastrous accumulation of gas fumes around and inside the vehicle that may misfire if the situation worsens.

Conclusion:

A false-functioning car may have any underlying reason, and the reason that doesn’t grab attention most of the time is a poorly working purge valve. It’s dangerous and can put you in some disastrous circumstances. To know if it’s your purge valve that’s causing the car’s malfunctioning, you can check it with the help of a multimeter.

Testing is painless, commendable, and worthy as a car with poor EVAP and Purge Valve can be riskier!

Read More: How to Test Capacitor using Multimeter

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