Gas Fumes
 

The other day my wife asked me if I smelled gas fumes when we were parked but I did not at that time. Now I have been driving and randomly smelling gas and it freaks me out a bit. It seems to occur when I do city driving: a lot of stopping/going/heavier acceleration. I have not noticed any leaks nor do I smell any gas fumes coming from the exhaust (like I would if it were running rich maybe? But I have a CAI so I should be lean if anything...). Nor does the engine compartment smell of any fumes while running with the hood up.

I run 88 octane because the alternative is 86. My best theory is that I may have a leak at the top of the tank and the sloshing from city driving is causing spillage. Anyone have any other theories, sources or tests I could do to locate a leak? Or does heavy acceleration create a temporary gas fume from extra fuel injection? And when I say "heavy acceleration" I do not mean pedal to the medal-just 3-4k rpms to scoot in and out of traffic where I need to.

might be leaking on top of the gas tank

check and see if you have any leaky injectors.

Rev it a little bit with the hood open (just twist the throttle in the engine bay), and see if the smell turns up. I would guess it's one of those little seals on an injector, cause if there was a leak from your tank you'd be throwing a SES light.

also look for wet spots around the injector ports.

Could be a leaky Fuel Pressure Regulator. Mine went out and you could smell gas through the vents when parked.

Thanks all. I'll check on those tomorrow. For a quick reference: where is the fuel rail on the 3400?

I'm especially interested in the regulator part. That is when I can smell it the most: when I am stationary.

^ If i Recall... Its under the LIM on the 3.4... But I dont know the 3.4 too well, so dont take me word for word.

its under the UIM that says 3400 SFI on it, you will see the fuel rail with all the injectors.

and the fuel pressure regulator is on the right with a vacuum line on it

http://www.youtube.com/watch?v=UHTV3W5VI5w
http://www.youtube.com/watch?v=cUIIn32nlvA

and dont tap your injectors!! its just to show you where they are!!! please dont snap your injectors

Interesting vids. Thanks scott. No issues with mpg (27-28 mpg) or stalling or hard starts...Gonna call the shop just to be sure and have her looked at. We'll see if it still happens today or if I am imagining it. Placebo effect ya'know?

I was expecting this thread to be about the aftermath of a trip to Taco Bell.



Seriously, when I had this exact same problem happen to my Escort, it was the fuel filler tank hose (flexible hose between the metal fuel filler piece and gas tank). With the gas tank level at the appropriate level it's only noticable when takeing a turn. If the hose gets bad enough, gas will spill right out when doing a fill up. It would explain why you aren't seeing or smelling anything in the front of the car or with the hood up. I was smelling gas everywhere but from under the hood, and it was very consusing. The offending bad hose looked like this:



When I say the problem was confusing, it was because mine was at the beginning stages of being bad. If you wait long enough and the hose gets worse, you'll easily notice a gas puddle when filling up the car. I know you stated no MPG problems, but this hose could have just gone bad.

It's easy enough to check.

My question is why are you running 88 octane?

The recommended octane is 87 I know this to be true. But in El Paso the octanes only go by 86, 88 and 91. So I figure it is better to be an octane up than an octane down.

Z-that is actually really good input. I drove quite a bit today, took it easier on the throttle which is to say I tried to keep everything around 2k rpms or less and had no problems whatsoever. I went to get a haircut, pulled a sharp and fast U-turn, parked a minute or two later and hot damn! Gas smell up near the front driver side that seemed to be coming from the engine compartment. Though it could have been from anywhere it was strong enough. Pulling out of the parking lot I heard a strange sloshing sound from the front I had not heard before...

I am beginning to worry that I am going to randomly combust.

Check the fuel filler hose, even though it's at the back of the car.



I also wondered if I was driving the Hindenburg.

pshh......that's a crock, I used 85 for years and never had a problem......

Ease up now. I didn't say I had a problem with the engine running on 86. But if I had to choose between going above or below the recommended standard I choose to go above. But I wonder if going a little higher could produce some extra fumage that would not be there on the standard.

And for a gas leak to have enough fumes to smell up in the interior there would have to be a pretty substantial leak. And for that kind of leak shouldn't I be throwing codes for there being a break in the vacuum? Such is what a mechanic said to me today. Makes sense.

Beginning to wonder if it isn't in my head or something.

not always, I had a leak from when I broke my fuel line ( very very very small crack in it ) and I could smell it in the car yet it was on the fuel filter but I could only smell mine when the car was stopped

When my fuel filler hose broke (pictured above) I got no codes. The whole thing was confusing until I bothered to look at that hose. I did think (at times) that it was somehow leaking into the car as well, and on an Escort, at least that's more plausible since you do remove the back seat to get at the fuel pump.

No you wouldn't get extra fumes because I run 89-93 in mine year round, and I've never smelled gas.