Originally Posted by jmjames66

I too am having the "Check Gas Cap" Msg on DIC. Will get codes and check into Fuel Vent Solenoid. Question: Are those Flowmaster Mufflers in your pics? Super 40 series? How are you likeing them? Got the same thing. Just curious...

Thanks,
Jeff

Originally Posted by corvet786c

Actually I believe I just Fixed mine with no new parts. I took the canister out yesterday and cleaned it out real good, (was very dusty inside). Reinstalled it, just disconnected the battery and waited like 30min to reset SER ENG LITE. Did a couple of runs and no service engine lite on.

Originally Posted by jwf

So great write up! .. and Fantastic pictures! .. but I'm left with a question on the venting system operation that maybe those of you with more experience can shed a light on. It makes sense to me that if the Fuel Vent Solenoid is stuck open that it means vapors are allowed to escape without going to the canister... much like a faulty gas cap. So my question is; does the fact that there is a vent solenoid mean that at times we allow venting of the vapors? It just seems odd to design a system to contain the vapors but then to add a soledoid to bypass the system.... but I'm sure there's a reason

Originally Posted by Shortimer

Hi John,
Do you have the AC Delco part number for the fuel vent solenoid you replaced back in Oct. 2012? Great write-up and photos.
I'm getting the same error code with my '08 and replacing the gas cap did not fix the issue. I'll try the fuel vent solenoid next but I'm coming across different part numbers.
Thanks,
Dan

Originally Posted by Razrback16

Is removing the wheel a must? I am curious because I have heard that the C6s are sensitive as far as their tire pressure sensors. Is there the possibility that the PCM will have issues with the tire pressure sensor if you pull the wheel?

Thank you in advance.

Originally Posted by JPSlick

I ended up doing this tonight.

Originally I jacked the car up as per the DIY thinking it was nearest the wheel well and I wouldn't need to be physically under the car. That was further from the truth. This is actually right above the over axle pipe just behind the passenger side muffler.

I ended up taking out the Race Ramps and driving the car right up on those instead. MUCH easier.

After a bit of fighting with the Evap hose and getting the unit off the dog ears it was finally free.

Although I ran into one snag. My new fuel vent solenoid has a square plug in shape and the old one was shaped like two half moons like the DIY.

The plug goes in but not seated fully. I'm thinking I need the latest harness but I currently have no codes so I believe it works for now. I did order the harness anyway but apparently it was on back order. It should be a quick fix as the harness seems even easier then fuel vent solenoid. All in $64 Shipped (Gas cap, Solenoid, Harness).

I also replaced the gas gap since my car is a 2006 and it was just old. Car has only 16K miles though.

Originally Posted by JPSlick

I ended up doing this tonight.

Originally I jacked the car up as per the DIY thinking it was nearest the wheel well and I wouldn't need to be physically under the car. That was further from the truth. This is actually right above the over axle pipe just behind the passenger side muffler.

I ended up taking out the Race Ramps and driving the car right up on those instead. MUCH easier.

After a bit of fighting with the Evap hose and getting the unit off the dog ears it was finally free.

Although I ran into one snag. My new fuel vent solenoid has a square plug in shape and the old one was shaped like two half moons like the DIY.

The plug goes in but not seated fully. I'm thinking I need the latest harness but I currently have no codes so I believe it works for now. I did order the harness anyway but apparently it was on back order. It should be a quick fix as the harness seems even easier then fuel vent solenoid. All in $64 Shipped (Gas cap, Solenoid, Harness).

I also replaced the gas gap since my car is a 2006 and it was just old. Car has only 16K miles though.

Originally Posted by JKbride

Driving down the road and you see "Check Gas Cap" warning come up on the Drivers Info Center (DIC)...take heart, it's an easy fix and does not take much time or money to repair yourself.

First, check your fuses and your gas cap. The cap should be on good and make sure it's secure. Tank up and drive your car for about 50 miles. If the code does not clear you should replace your gas cap. I purchased one from my local Chevrolet dealer for $22.

Secondly, if after tanking up and replacing your gas cap the warning does not clear, then it's time to use your trusty code reader and see if you can't read and clear the code. If you don't have one you can purchase them at your local parts store for about $50.

Plug it in the OBD adapter located under the driver’s side dash.


Follow your reader’s instructions and read the codes.

In my case I had a P0449 and a P0455. P0449 Evaporative Emission Control System Vent Valve/Solenoid Circuit Malfunction and P0455 Evaporative Emission Control System Leak Detected (gross leak)



I tried resetting my codes, but they would come back within seconds. The next step is purchase a new Fuel Vent Solenoid from your local dealer. In my case it was about $25. GM also recommends an upgraded harness ($30)...but it was not needed, so I will return it.


The Fuel Vent Solenoid is located on the passenger side tank near it’s top and is easy to get to. I removed my rear tire, jacked up the car, placed jack stands and chocks (I'm super cautious under a car).



Once under the car this is what you will see, and I have my finger on the part:


Remove the Vent Hose (it runs to your emissions canister) using a pair of pliers. You can rotate the clamp if needed to access the dog ears to open the clamp.



Unplug the power connection


Slide the Vent Solenoid Assy of its bracket. Although it looks like it would slide towards the front of the car it does not. Simply lift the back of the assy high enough for the dog ear to clear the back of the bracket and slide toward the rear of the car. The pic below shows you how it mounts and the dog ear location.


Put the new Vent Solenoid Assy back on by placing it on the bracket and slide it towards the front of the car. You will hear it click in place. Plug the power plug back in and reconnect the hose.

Here is the new one installed.


Now plug your code reader back in and scan for codes. If they come up hit erase.

This is what you should now see on your code reader. No Codes and the DIC is clear with no check engine light or warnings.



From start to finish the repair took 20 mins. The cost of the parts, including gas cap was about $50 and if the harness is needed it's about $80. If you don't have a code reader add another $50. Only tool needed is a pair of pliers.

In all this is a simple repair and does not cost much in terms of time or money to do yourself.

I hope this helps,
John

Originally Posted by JKbride

Pete I'm glad this was able to help you. Anytime I do something to my car, I always try to take the time to do a DIY thread.....it's just a small way to give back to the community that has helped me along the way too