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Smell of gas in rear

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Old Dec 27, 2009 | 01:21 PM
  #1  
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Smell of gas in rear

Hey guys 88 GTA - I have noticed a smell of gas after the car has reached norm operating temp. It is most prominant about the driver side wheel (got to put my head in the wheel well itself). I checked the filler neck and it seems like it's still attached without a problem. Is there any easy wAy to figure out where it's coming from? Thanks guys.
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Old Dec 27, 2009 | 02:18 PM
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Re: Smell of gas in rear

My wife often complains about the smell of gas in my rear!

I read alot on hear about the filler necks leaking and also getting slightly seperated from the tank when folks work too hard at removing the tank for fuel pump replacement. Is there alot of presure when you remove the cap? Maybe the vent atop the tank is clogged and so pressure is releasing at the cap - might try a new cap and checking the vent under the car that comes out of the tank top.
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Old Dec 27, 2009 | 02:36 PM
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Re: Smell of gas in rear

Thanks. I am pretty sure the filler neck is still secure. in order to hear the pressure release from the cap, do I have to drive it around for a while to warm it up or should I be able to take it off anytime? And you r saying that if I hear a lot of pressure then the tank vent might not be good? does that meAn I would have to remove the tank?

Last question- whAt if there is little to no release of pressure at the cap end? Then what could I check?
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Old Dec 27, 2009 | 04:38 PM
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Car: 82 TA 87 IZ L98 88 IZ LB9 88 IZ L98
Engine: 5.7TBI 5,7TPI 5.0TPI, 5,7TPI
Transmission: T5, 700R4, T5, 700R4
Axle/Gears: 3.08, 3.27, 3.45, 3.27
Re: Smell of gas in rear

I was pretty sure my tank wasn't leaking but I could smell raw gas a mile away. When ripping the car apart I saw the solder joint where the filler tube meets the tank leaked like a MF
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Old Dec 27, 2009 | 05:14 PM
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From: Cary, North Carolina
Car: 1992 RS
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Re: Smell of gas in rear

Don't have to drop the tank to get to/replace/repair the vent - it clips on the frame right at top of the tank - just follow the fuel lines from the filter back and you'll see it.

I'm not sure how it's supposed to be - when my RS was stock, I always had pressure release when opening the cap - but since I went carb and yanked out the charcoal canister I have no pressure release.
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Old Dec 27, 2009 | 09:42 PM
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Re: Smell of gas in rear

Hmmm - OK...thanks for the tip. I'll see if I can find that vent. If / when i DO find it though, how can I tell if it's bad?

I did take the car for a ride and then upon parking loosened the gas cap. A ton of pressure was released (a lot more than I'm used to hearing from my newer model daily drivers anyway). Does that inherently say anything?

(P.S. it's fuel injected)
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Old Dec 28, 2009 | 09:02 AM
  #7  
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From: Cary, North Carolina
Car: 1992 RS
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Re: Smell of gas in rear

I don't know how you'd know it was bad or good - it was just my crazy thought LOL.
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Old Dec 28, 2009 | 10:02 AM
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Re: Smell of gas in rear

The hardest place to look is on the lines coming out on top of the gas tank but that's where it was leaking on mine.

Little cracks between the steel lines and the "lid" that locks down. For a temporary solution I poured some JB weld all over the lid and let it dry for a day. Over a year later and still no more smell.

I'll replace the whole assembly the next time I do the fuel pump.
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Old Dec 29, 2009 | 08:09 PM
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Re: Smell of gas in rear

Update - I replaced what in my mind was the easiest and cheapest (and most logical) - the fuel pressure relief valve. I got a new one from GM and popped it on. Let the car warm up for a few, and then drove her around the block for five minutes or so. Normally I could get right out and smell the gas from the inside of the rear wheel well. Today I smelled nothing. Don't want to jinx myself and say it's officially fixed, so all I'll say is 'the new valve appears to have resolved the problem of the fuel smell'. Won't know for sure until I can drive for longer periods. But for anyone who had my situation (smell of gas coming from the driver's side rear wheel area), try this first. It might very well solve your problem. THANKS FOR ALL YOUR HELP GANG!
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Old Dec 29, 2009 | 08:15 PM
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Car: 1992 RS
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Re: Smell of gas in rear

Glad it "appears" to have worked out!
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Old Dec 29, 2009 | 08:40 PM
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Re: Smell of gas in rear

you might also put some heat shielding between muffler and fuel tank....pretty cheap and easy to install.....keeps some of the heat off the fuel tank......will help with that high pressure on those hot summer days sitting in traffic....sometimes I think my tank is going to explode there is so much pressure in there, lol
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Old Dec 30, 2009 | 08:40 AM
  #12  
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Re: Smell of gas in rear

Originally Posted by joef2002
Update - I replaced what in my mind was the easiest and cheapest (and most logical) - the fuel pressure relief valve. I got a new one from GM and popped it on.
I've been following this thread since I sometimes have the same problem. Where is the fuel pressure relief valve located? Was it a big job to replace?
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Old Dec 30, 2009 | 10:08 AM
  #13  
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Car: 82 TA 87 IZ L98 88 IZ LB9 88 IZ L98
Engine: 5.7TBI 5,7TPI 5.0TPI, 5,7TPI
Transmission: T5, 700R4, T5, 700R4
Axle/Gears: 3.08, 3.27, 3.45, 3.27
Re: Smell of gas in rear

The white thing in this pic. It's in front of the axle, drivers side where the fuel lines run up to the tank.

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Old Dec 30, 2009 | 09:50 PM
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Re: Smell of gas in rear

Gracias. If it ever warms up around here I will get under my car and take a look. Supposed to go down to the mid-20's this weekend. I know that many places are regularly colder than this, but Florida temperatures have to be translated, sort of like "dog years".
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Old Dec 30, 2009 | 10:09 PM
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Car: 1992 RS
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Re: Smell of gas in rear

Twin_Turbo:
Where's the dirt at? I don't see any dirt under there! Not even a speck of surface rust! Is that a trailer queen ya got there?

vette:
Come on now - Man Up! It was 23 here this morning when I left the house, and I rode the motorcycle to work!
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Old Dec 30, 2009 | 10:13 PM
  #16  
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Re: Smell of gas in rear

Originally Posted by camaronewbie
vette:
Come on now - Man Up! It was 23 here this morning when I left the house, and I rode the motorcycle to work!
Like I said, you have to translate temperatures for Florida. I spent most of my life in upstate New York and Pennsylvania where negative temperatures weren't uncommon in winter and it was no big deal. After 15 years in Florida, though, I really can't stand the cold.
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Old Jan 1, 2010 | 09:16 PM
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Re: Smell of gas in rear

HOLY CRAP TWIN! I snapped a pick of my valve but am now embarrased to even upload it. How the hell do you keep that underside so clean!?

Vette - you'll see it in Twin's pic there. it's that white plastic thing right there in the center of the picture VERY easy to replace. Just loosen the clamp that holds it on and slide the valve off of the hose. No pressure issues, no gas leaking, nothing. Just don't make the mistake I made though and leave it off for a day. The fumes from the tank will pour out that hose if no valve is there. I walked into my garage and thought it was going to explode. So keep the valve on until you're ready with a new one to repalce it. Easy peasy. Good luck!
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Old May 22, 2010 | 01:46 AM
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Re: Smell of gas in rear

Aloha,
Mahalo for the pic, it always tells 1,000 words, and saved me and the parts guy alot of time.
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Old May 22, 2010 | 08:42 AM
  #19  
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Transmission: 700R4
Re: Smell of gas in rear

Originally Posted by Hawaiian
Aloha,
Mahalo for the pic, it always tells 1,000 words, and saved me and the parts guy alot of time.
Where did you get it and how much?
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Old May 22, 2010 | 10:35 PM
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Re: Smell of gas in rear

I ended up getting the part direct from a fm parts dealer in my area. Guess itsnone of those items u can still find new at the parts counter !
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Old May 23, 2010 | 03:18 AM
  #21  
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From: Enschede, Netherlands
Car: 82 TA 87 IZ L98 88 IZ LB9 88 IZ L98
Engine: 5.7TBI 5,7TPI 5.0TPI, 5,7TPI
Transmission: T5, 700R4, T5, 700R4
Axle/Gears: 3.08, 3.27, 3.45, 3.27
Re: Smell of gas in rear

Originally Posted by camaronewbie
Twin_Turbo:
Where's the dirt at? I don't see any dirt under there! Not even a speck of surface rust! Is that a trailer queen ya got there?

vette:
Come on now - Man Up! It was 23 here this morning when I left the house, and I rode the motorcycle to work!
No, it's a complete rebuild and it's not done yet. Looked like this before:

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Old May 27, 2010 | 09:26 PM
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Re: Smell of gas in rear

what is the name / part number of this fuel pressure releif valve I am having troubles searching it out on the magical internet.
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Old May 28, 2010 | 07:41 AM
  #23  
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Re: Smell of gas in rear

Originally Posted by Malderun
what is the name / part number of this fuel pressure releif valve I am having troubles searching it out on the magical internet.
GM# 10033125

It is referred to as Valv Asm on the box.

RBob.
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