gas smell

[Crystaline109]

ok so as some of you know, i'm new to imprezas. But i'm also new to turbo charged cars in general. I've read Corkey Bell's "maximum boost" book from cover to cover (REALLY good book) so i have a theoretical knowledge of tubro systems.

Ok enough backround, here's what happened.

While taking my 06 WRX up a dirt road into the mountains, my GF started to smell gasoline. Faint at first, but then it got stronger and stronger till the point it was making both of us nausius. So i pull over to try and smell where it's coming from and it seems to be strongest comming out of the exaust pipe. we were about 6 miles up this trail. so i figure it's a good time to turn around. on the way down the gas smell slowly dissipates, and by the bottom of the trail, there is no gas smell at all.

My conclusion (please tell me if this makes sence)

While heading up the trail, (a nearly constant uphill, steep at times), I was on and off the throttle alot, mostly in second gear. I would get the car solidly into boost then get off the throttle for a blind turn or rough terrain. This caused the car to run rich every time i let off the throttle and unburnt gas started to accumulate in the exaust (cats/muffler everything is stock). Now since i never really got above 35mph, the fumes wafted back into the car. on the way down, i didn't use the throttle at all really, allowing the unburnt gas to dissapate.

Does this sound at all plausable? am i overanalizing the smell? or is this indicitive of a bigger problem?

[pcowan]

It's possible. Is your car modded at all or bone stock?

[Crystaline109]

bone stock

[rollo]

I'm gonna say that if you were smelling it in the car strong enough to make you feel sick, it was coming out of somewhere other than the exhaust (unless you had the hatch open :) )

Usually a strong gas smell is indicative of a leak, simple as that. Kinda scary. Here's my thought: there's a loose clamp somewhere, and in the constant on-throttle/high boost situation (= higher fuel pressure) some gas ended up being forced out under the clamp. On the way back down, you're not on the throttle as much and the standing (smelly) gas slowly evaporated.

I guess another possibility could be a dirty fuel filter (or some other partial blockage) causing pressure to build up and forcing gas out of whatever is the weakest point in the system. Given that the car was pointing nose up, since you were going uphill, if the forced-out gas trickled backwards it may have seemed like it was coming out of the exhaust.

Could also be a pinhole leak in one of the fuel lines - less likely, since the car is not very old.

If I were you, I'd be changing the fuel filter and checking for tightness on the fuel line clamps/clips. It can't hurt.

It's not something to procrastinate with though, if the fuel gets on a hot downpipe or whatever it's gonna be a bad time for all involved.

WRXperts (I am not one) - feel free to poke holes in my theories.

Let us know what you find out.

[MConte05]

The bugeyes are well known for fuel leaks in the winter due to loose clamps on the fuel lines. Something that one is really only able to do either under warranty or when you take off the intake manifold. When I took mine off I tightened all the clamps, it was a pretty sorry state when I could almost tighten the clamps with my fingers because of how loose they were. However on the newer models I am pretty sure they fixed that problem. I can't really think of anything that would cause those issues to come up.

:shocked:

[Crystaline109]

ok i'm gonna have to find a way to stress the fuel system without getting a ticket. Guess i'll look for a cloverleaf of some kind to play with.

[Obsidian]

MConte05 may be right. I have an 05 RS and had the same problem. Mostly at idle and slow speeds, especially when the engine was cold. I had to do some work which required the intake to be removed. When I checked the hoses I was surprised to find how loose the clamps were. I replaced the hoses (168,000 miles, felt it was due) and haven't had the problem since. You may want to check the top of the engine for puddling of gas when you begin to smell it. It should accumulate right under where the hoses meet the pipes. Good luck.

[snaggleto0th]

Ya it DEF. sounds like the fuel line is leaking underneathe the manifold. Its a real PIA to do but its not to expensive(as long as Subaru gives you the RIGHT gaskets). As Obsidian said, check ontop of the engine around the turbo inlet area(thats where I found mine) and any where on top of your engine. But ya good luck on it, shouldnt be to hard to find the leak just go by the smell of gas. If you cannot get it to leak let it sit over night, turn the key on, key off, key on, key off, dont start. Ally your doing is getting the fuel pump to prime the system and it SHOULD leak. Mine did at least I do have a 02 Bugeye..again good luck!!

[Savenfiddy]

ok so lol, my 07 as well as my friends evo X both gas the strong gas smell when it gets really hot outside. from what i understand our cars are equipped with a fuel evaporation purge system. By swapping out "air by-pass hose B" with a collapsing fuel EVAP line you can immediately eliminate the heptane insoluble portion of the evaporation residue of motor gasoline from sticking to your intake tract while it's hot at wide open throttle. **Heptane is a zero octane gas! Heptane is not compression friendly and ignites under minimal compression. The collapsing fuel evap hose expands and contracts to open and shut the return of fuel evaporation from the purge solenoid. Under heavy pressure from wide open throttle and turbo boost, the line seals shut eliminating heptane purge. When the car is at idle or easy daily driving, the line remains open allowing regular fuel EVAP purge functions to continue so the vehicle will meet emissions. ( This is where i found my info, i still want to get the hose replacement) http://subaru-offroad.blogspot.com/2009/07/easy-wrx-mod.html

[Savenfiddy]

http://www.examiner.com/x-4824-Tampa-Sports-Car-Examiner~y2009m6d27-Cheap-WRX-mods-collapsing-fuel-EVAP-line another article about the same subject from a diff source

[u3b3rg33k]

Amusingly, at 183,000 Miles, I had a fuel line start to fail (ie bleed fuel). I was on the way to somewhere important, and figured that if I could smell fuel, something bad would soon happen. I returned home to swap cars. After replacing the bad fuel rail supply hose (and the other ones that didn't look great), I had to re-tighten the new clamps after a few hundred miles, and all is now well.

good call on heading back down, I'd hate to read a thread titled "gas smell - car fire".

[Crystaline109]

ok little update. i've driven the car hard on the road home from work (take it up to 4500rpm in first, shift to second, then either be WOT or coasting... i prolly looked like a lunatic, but i'd rather appear strange than catch fire) under these conditions there was no gas smell. I did the on off on off on off thing mentioned by snaggle, and there was no leak or drip by the fuel rail.

BUT, every time i turned the key to the ON position, the fuel tank made a slurping sound... kinda like a kid drinking a milk shake through a straw, when they start to suck both air and milkshake... i know hard to discribe. but it was definatly comming from the tank itself and it does it every time (i have a half full tank... so it's not empty for sure)

is that normal? is that a possible source? it's an 06, so i'm just keeping my fingers crossed that it's not the issue the bugeyes have...

I'm gonna try and go up another dirt road into the mountains either tonight or tomorrow and see if i can get it to make the smell agian, try and pinpoint it's source.

[97ScoobyL]

everytime you turn the ign switch to on the fuel pump primes for 2 seconds.

[Crystaline109]

everytime you turn the ign switch to on the fuel pump primes for 2 seconds.


so it would make a slurping sound? just seems.... peculiar.

i'm just hoping it's the evaporator line, since it never does it at idle or anything below wide open throttle. since that romp was the only time i've really gotten on the throttle for more than a freeway entrance ramp.

[rollo]

A slurping sound could indicate a leak somewhere in the lines, if it's sucking air as well as fuel.

I think your best bet is to try and diagnose it in a garage or something, somewhere with a fire extinguisher ideally. The fuel fumes will "pool" if the car is standing still, and you can watch for leaks/drips and stuff. It may be happening to a lesser extent at lower revs, but you just can't smell it inside the car until it's really serious. Which is bad.

http://www.eaminer.com/x-4824-Tampa-Sports-Car-Examiner~y2009m6d27-Cheap-WRX-mods-collapsing-fuel-EVAP-line another article about the same subject from a diff source

That's the same source as the other article.. it's that guy who was here on DI for a while earlier this year, then got all pissy and changed all his posts to "ass". Dunno how much I'd trust his stuff to be honest.

[sebhockey]

Check your charcoal canister, it may not be connected properly or may have become damaged. If either is the case it would be why you can smell gas inside your car. It's the weird black box under rear part of you car near the filler tube making it easy to damage.

[Crystaline109]

Check your charcoal canister, it may not be connected properly or may have become damaged. If either is the case it would be why you can smell gas inside your car. It's the weird black box under rear part of you car near the filler tube making it easy to damage.


so THAT's what that thing is...

i ran the car at idle in my garage with the door almost all the way closed (so there was no wind) and my butt smelt more than the car even after 30 min. I'm gonna shoot up rampart road this afternoon and see if i can even get the car to make the smell again... who knows, maybe i accidentally bought christine :shock:

[u3b3rg33k]

No CO poisoning? guess your cat works.

[Savenfiddy]

A slurping sound could indicate a leak somewhere in the lines, if it's sucking air as well as fuel.

I think your best bet is to try and diagnose it in a garage or something, somewhere with a fire extinguisher ideally. The fuel fumes will "pool" if the car is standing still, and you can watch for leaks/drips and stuff. It may be happening to a lesser extent at lower revs, but you just can't smell it inside the car until it's really serious. Which is bad.



[QUOTE=rollo;149016]That's the same source as the other article.. it's that guy who was here on DI for a while earlier this year, then got all pissy and changed all his posts to "ass". Dunno how much I'd trust his stuff to be honest.

lol i did not know that.

[snaggleto0th]

Well if it were a EVAP leak or a EVAP hose the computer would of set the check engine light especially it being a 06 its a CANOBDII system and those systems can detect a evap leak pretty damn good.

Theres either a intermitent leak such as a fuel injector or fuel line so that when it gets hot(i.e; going up a mountain WOT for a while) the metal expands and creates a small opening for fuel to leak out. It sucks but to diag that you must let it idle in a safe place so if fire happens(it might) your prepared to take it out.


The slurping noise you got me beat is this underneathe the car you hear the noise or inside the truck where you can access the fuel pump? I had a caddy CTS make a really akward noise in the rear near the tank and it happened to be a fuel cap was broken and shaking, replaced the cap and noise went away!