Do you ever wonder why your car’s engine warning light keeps coming on, or why your vehicle is losing power and fuel efficiency?
The problem could be due to a dirty or clogged purge solenoid valve. This small but crucial component of your car’s emission system can have a significant impact on your vehicle’s performance and can even cause long-term damage if left unattended.
Fortunately, cleaning the purge solenoid valve is a simple and affordable task that can be done at home, with no special tools or skills required.
In this blog post, we’ll guide you through the steps on how to clean purge solenoid valve. So, if you’re looking to improve your car’s performance, reduce emissions, and save money on costly repairs, read on!
Table of contents
What is The Job of A purge Solenoid Valve?
The job of your purge solenoid is to open up when your car’s PCM commands it to and allow for the hydrocarbons or fuel vapers that are deposited into your charcoal canister from your fuel tank to be directed back into the engine through the vacuum that’s inside your intake manifold.
If you think your purge solenoid has gone bad, It’s best to carry out some tests first before trying to clean it up or spending money on another one.
How to Test A Purge Solenoid Valve
In order to test a purge solenoid valve to see if it’s working or not, these are the tools you’ll need:
- A vacuum hand pump
- A 5/8 inch rubber hose with clamps at both ends
- A multimeter
- Battery power supply
1. The Audible Click Test
Clamp the red battery supply cable to the purge valve terminal. Use the green cable to make contact with the same purge valve terminal and see if it produces an audible click.
2. Test To See If The Valve Closes Properly And Doesn’t Leak
To carry out this test, attach the 5/8 hose to the hand vacuum pump. Tighten the clamp at the point where the hose attaches to the vacuum pump very well to ensure there’ll be no leakage.
Connect the other end of the hose to the purge valve part which goes into the intake manifold on the engine. Tighten the clamp from the hose at that point properly as well.
Now, pump the vacuum up to 15 in Hg vac (inches mercury vacuum) and see if the valve can seal properly. Let it sit for around 5 to 10 minutes and see if the vacuum gauge would drop. If it drops, it means that the purge valve is leaking.
3. Test for Continuity Using The Multimeter
The reason you have to carry out this test is because of the fact that a solenoid is just a single continuous coil of wires. It can be tested for continuity to see if it is open or not.
Step #1: Set your multimeter to continuity (ensure that you see the little speaker symbol on your multimeter screen)
Step #2: Use the two cables from the multimeter to make contact with the purge valve terminal.
If you hear a continuous sound from the multimeter, then you know that your purge valve has continuity. It’s not an open circuit.
4. Test for Ohm Resistance Readings
Step #1: Set your multimeter to ohms reading
Please note that the resistance reading of purge solenoid valves can vary based on the make and model of your vehicle. But overall, the resistance should be somewhere around 30 ohms.
Bad Purge Valve Symptoms
The purge valve is a part of the evap system. Its purpose is to open up and transfer fuel vapors from the charcoal canister and into the engine where it gets burned off in the combustion chamber. This helps to reduce emissions and increases your miles per gallon.
Below are some of the symptoms of a bad purge valve:
1. Check Engine Light On
One of the symptoms you’ll notice when you have a bad purge valve is that you’ll have your check engine light on. This will be accompanied by some of these codes: P0441, P0443, P0444, or P0445.
Now, you can read these codes by going to an auto parts store near you and they’ll most likely do it for free. Or you can buy a scanner and check them out yourself.
You can still have a faulty purge valve with no check engine light on. So let’s move on to the next symptom.
2. Rough Idle
If the purge valve gets stuck open, then the excessive fuel vapors will flow into the engine. This creates a rich condition since there’s more fuel than air in the combustion process.
In order for the car to run at its best, it strives to achieve the perfect air/fuel ratio. A faulty purge valve disrupts this fuel ratio. This is why you have a rough idle.
3. Poor Engine Performance
Similar to a rough idle, if your purge valve is stuck open, it’s going to disrupt the air/fuel ratio creating more fuel than air in the combustion process. That’s exactly why you notice your car feeling more sluggish than usual.
4. Hard Start After Putting Fuel In Your Car
The reason for this is that fuel will occupy more space in your tank. This forces fuel vapors to go past the stuck open valve and into the engine. This creates an excess of fuel when starting your car. And as you know, too much fuel with too little air causes a no-start.
5. Poor Gas Mileage
The reason for this is that the purge valve will consistently be bringing fuel vapors into the combustion chamber. A good purge valve will stay closed and only open up when it’s commanded by the ECM.
Related Post: Spoon Engine
How To Clean Purge Solenoid Valve
In cleaning a solenoid valve that has failed all the tests we listed above, it’s important to be very careful about the kind of cleaner you use. Avoid using generic parts cleaners, carb/choke cleaners, or brake parts cleaners.
Instead, use a mass air flow sensor cleaner. This is much safer for plastic (which is what your purge solenoid valve is made of).
Cleaning the purge solenoid is very easy:
- Step 1: Just spray the mass air flow sensor cleaner with a closed valve technique
- Step 2: Connect a 12volts battery source to the valve’s terminal and spray again with an open valve technique
- Step 3: Leave the valve to dry
- Step 4: Once the valve is dry, ensure that it’s completely dry by blowing a vacuum hand pump over it to dry up any traces of the mass air flow sensor cleaner.
Once you’re satisfied that it’s totally dry, reinstall your purge valve solenoid, restart your car and see if the check engine light is still on.
At this point, the check engine light would definitely go off and your car performance should go back to normal.
Conclusion
In conclusion, cleaning your purge solenoid valve is a crucial step in maintaining the health and longevity of your vehicle’s emissions system. You can save yourself time and money in the long run while also reducing your carbon footprint by following the steps outlined in this post.
However, beyond the practical benefits of cleaning your purge solenoid valve, it’s worth considering the bigger picture. The emissions from our vehicles have a significant impact on the environment, contributing to issues like air pollution and climate change.
While cleaning your purge solenoid valve is just one small step, it’s part of a larger effort to reduce our collective impact on the planet.
Ugo is a passionate car enthusiast with a Bachelor of Electrical and Electronics Engineering degree and hands-on experience in troubleshooting and fixing automobiles.
I combine my electrical and mechanical engineering knowledge with practical skills to address car-related issues.
My love for cars and dedication to educating others led to the creation of Fixandtroubleshoot.com!
