Has anyone figured out why the Evap Purge Valve fails?

I replaced one last summer and today I got P0497 this morning with a hard cold start.

Figured it's likely the cause.

 

I believe the purge valve fails due to sudden airflow/pressure shooting through it the wrong way when we go into boost. A while back I attempted to embed a check valve inside solenoid or before the solenoid, in the tunnel going to the IM bowl, but was unable to find a good way of employing it.

The solenoid is quite hollow inside the top half of it, in addition to not having a check valve until halfway up the evap line in the engine bay. That means that there's that much possibility for that volume to be backflowed and then pressurized when you go into boost. Higher boost levels or quicker hits of boost would seem to make it more prone to breaking.

There have been times when I turn off my car and a sudden spurt of air pressure was released by it a few seconds later. It also explains why we have sudden AFR wobbles with it sometimes. It builds up pressure between it and the in-line check valve and then releases it along with air-fuel vapor mix the next time it opens, causing the engine to get more air-fuel vapor then it bargained for.

If there's a way to install a check valve between the IM and solenoid, I believe the problem would be solved.

 

Got my first P0497 this morning. No sound accompanied its arrival and I was driving like a grandma too...

 

yeah, i removed the entire system no emissions checks in florida

 

wooooooah,
give me the details of how you removed it.
I live in bradenton florida, and have changed the damn purge solenoid 3 times, and my "check gas cap" came on tonight again, so the rough idling and such will follow like always.

 

Sub'd for complete removal

 

Just remove all the EVAP components, cap or plug the vacuum source and call it a day. Turn off the EVAP check engine light codes in HPT.

My EVAP system is in my shed, right next to my cat and second 02 sensor

No emissions testing FTW!

 

I was about to post this same thread......I just recently replaced mine....lucikly still under warranty so didnt cost me anything except gas for the wifeys car to take me back n forth....LOL

Anyways so if its true the increase in boost pressure causes this then dam im going to be replacing it every year!

So what does it exactly do?

And just removing it wont cuz any issue? Just a CEL that can be removed with Hptuners?

 

lol I never had a problem with mine yet. 38k miles. But maybe its cause I rarely step on it.

 

I just called the dealership is my area and they said that the EVAP Purge Valve is not covered under the powertrain warranty. I figured it wouldn't be, and even if it was they would still say it wasn't...

Looks like I will need to replace it or just get it turned off with a tune.

 

Yes but technically it should be covered under the emissions warranty. Now they still probably won't cover it. Take it in, take off the purge valve, blow through it and show it's bad, then tell them to cover or it gets shoved up their ass.

On a serious note. Just do it yourself. It takes 2 minutes to test and replace.

 

I will look to do it myself...If my car even has one installed. I know that their is no catalytic converter so I am not sure if the previous owner just removed it and the dealership just cleared the codes before I bought it.

If anyone has a link to a good how to that would be awesome. Will I need a jack or any special tools to get access to it?

 

No it's super freaking easy. Don't stress over it. The purge valve is right on the intake manifold. Open the hood You need a 10mm socket.


No jacks no nothing.

 

Alright I removed the sensor and did the "blow" test and was unable to feel the pressure release or lower indicating that my solenoid/valve is still good.
Could it also be the electronics inside the solenoid that is busted...or worse the wiring leading to the solenoid.

 

I had mine replaced twice, I was stock (not tuned), but the car ran better with out it. (remove / unplug) I havent had the ole Balt SS for a year or so, but I remember that it would supposedly freeze one of your parameters due to the EVAP not being read? Someone even dynoed and had some gains without it also on the stock tune. Yep FL has no emissions, unfortunately for me I have a bunch of straight piped Rednecks around me, so it has it's downs also.

 

Well I think it could technically be stuck in the closed position as well. Mine were stuck open. I didn't see where you listed what symptoms you are having. CEL?

 

Symptom is the P0497 DTC. I had my manager use his code reader to clear it once and then it came back 4-5 days later.

I don't really notice any other symptoms, but the CEL is just staring me in the face every time I get in the car, and possibly hiding masking other codes that may be triggering.

 

Well i don't know how many miles are on your car or what your current budget it, but for 20 bucks it's worth a replacement.

 

I can afford $20 for this.
The car has 44k on it now.
This won't affect the trifecta tune my car supposedly has?

 

Nope doesn't affect the tune., just for reference I am on my 3rd one at 57k miles. So consider yourself lucky. If this doesn't fix the P0497 then the evap vent valve by the gas tank is the other culprit. It's also like $30 and easily replacable. I did a how-to on it. But when i had P0497 mine was the purge valve both times.

 

Any one got the part number for this^^^^

 

Cap it and leave the line VTA (put a filter on it to keep stuff out)

 

So cap the top of the purge valve and put a filter on the end of that line?

 

Yep

Make sure the cap is secured to the top of the purge valve thought so it doesn't blow/pop off or something. When I did this method, I used a vacuum cap from an auto parts store and put a ziptie around it to hold it in place after I discovered the cap popped off without one.

 

What kind of filter?