EVAP Leak - Fuel Smell - No Codes

[dasgeek]

I have had an intermittent fuel smell coming from my LX for a few years. It only happens under certain conditions - when the weather is warm (around 85F to 90F) in the early Fall (August, September, Oct) and after I have been driving for 30 plus minutes. When I park the truck, I smell a strong gas vapor. I check under the hood and can hear a sucking/gurgling/bubbling sound like bubbles through straw on top of the charcoal canister.

Here is a picture of the canister on the DS of the vehicle:

If I squeeze the air drain hose, the sucking/gurgling/bubbling sound stops.

Here I am pointing at the air drain hose I squeeze:

Obviously the vapors stop after the truck cools down. Problem is that the house is already filled with headache inducing gas odor (not making the family very happy).


Does anyone have any ideas on what might be going on? I have looked though the FSM for troubleshooting the system, but just looking for further thoughts from MUD.

 

[dasgeek]

Bueller? Bueller? Any thoughts anyone?

 

[Mike6158]

All I can tell you is that it's a common problem.

Common enough that it's in the FAQ (handy reference that I don't use enough)

Petrol Smell CURED!!

 

[dasgeek]

All I can tell you is that it's a common problem.

Common enough that it's in the FAQ (handy reference that I don't use enough)

Petrol Smell CURED!!

Thanks for the reply, but this is a different issue than the one in the FAQ. I have read that post and the entire FAQ. I have also done a lot of searching on MUD and other sites before I posted my question.

My issue is not fuel smill in the cabin. It is coming from the evap canister. The fuel smell is more of a problem in the garage after I park the truck.

 

[Mike6158]

Fair enough. I have heard the noises and seen a bunch of posts about this subject. That said... sometimes searching this site requires cryptographic skills (that I don't have).

I've been told that it's the evap canister and when you price a new one you'll understand why nobody replaces them. I was told by the PO to never top off my tank but he didn't explain why. Basically you are hearing the fuel boiling. It boils because it's hot AND under a vacuum. I would like to know why liquid fuel makes it all the way to the evap canister.

Hopefully someone that knows the cypher will post a link to the discussions

Here's one I started: Bad fuel smell while doing some light wheeling in the desert

 

[dasgeek]

Here's one I started: Bad fuel smell while doing some light wheeling in the desert

Thanks for the link. I remember seeing that thread at some point. seems like the same problem but they never resolve it.

I agree that it takes a very specific skill set to find the correct thread sometimes. There is just so much info on MUD.

I am hoping an EVAP expert might have some thoughts. I may have a bad vapor pressure sensor or switch. Clearly the EVAP system is venting fuel vapor when it is suposed to be closed. My understanding is that the vapor that is escaping should be captured and redirected. That abviously is not happening.

 

[MongooseGA]

In for the solution. My 1999 LX is doing exactly the same thing, down to the leaking sound you're hearing in the same spot. Generally in the heat, and after reading a few of the linked threads it does seem to be most prevalent after fueling up.

 

[Spike555]

Don't park it in the garage?
Replace the EVAP canister?

 

[dasgeek]

does seem to be most prevalent after fueling up.

I don't think I can associate it will a recent fill up but I am going to watch that more carefully now. I never "top off" the tank when filling.

Don't park it in the garage?
Replace the EVAP canister?

I do leave the truck out of the garage now, when I notice it vaping. It is when I do not notice and the entire house fills with fuel smell I have a problem.

I don't want to replace a $400 part without knowing it is the problem. I am going to follow the FSM troubleshooting for the pressure sensor and pressure sensor valve. I just wanted to see if anyone had some suggestions. I will report back if I learn any thing helpful.

 

[Spike555]

I don't think I can associate it will a recent fill up but I am going to watch that more carefully now. I never "top off" the tank when filling.



I do leave the truck out of the garage now, when I notice it vaping. It is when I do not notice and the entire house fills with fuel smell I have a problem.

I don't want to replace a $400 part without knowing it is the problem. I am going to follow the FSM troubleshooting for the pressure sensor and pressure sensor valve. I just wanted to see if anyone had some suggestions. I will report back if I learn any thing helpful.

No $400 part replacement needed, GM replacement, $60. It's all over the internet on how to do this.

 

[dasgeek]

It's all over the internet on how to do this

Well, I guess I am sorry that I don't know how to use this internet thing you speak of...

 

[Spike555]

Well, I guess I am sorry that I don't know how to use this internet thing you speak of...

Charcoal Canister - Great Option!

The link is for a 80 series, but the concept is the same. It will not be a direct bolt on fit, if that is what you are looking for you'll have to bite the bullet and buy the OEM one.

 

[medtro]

Hope this helps.

Charcoal Canister Replacement Option

 

[bentambling]

I don't think I can associate it will a recent fill up but I am going to watch that more carefully now. I never "top off" the tank when filling.



I do leave the truck out of the garage now, when I notice it vaping. It is when I do not notice and the entire house fills with fuel smell I have a problem.

I don't want to replace a $400 part without knowing it is the problem. I am going to follow the FSM troubleshooting for the pressure sensor and pressure sensor valve. I just wanted to see if anyone had some suggestions. I will report back if I learn any thing helpful.

Were you able to solve this? I have the exact same problem