Slight fuel smell? Debug/troubleshoot...

I had a very slight fuel smell when sitting at an intersection earlier today.

Came home and parked the car, smelled around the back - nothing.

The fuel block recall has been done...

How to troubleshoot next steps? Is there a guide of step by step what to look for before taking the car in?

Thanks.

 

Could have been another car or just a vent burp

Keep a good eye on it dont mess with gas

 

And while you're in the troubleshooting process, make sure you have a good Halon fire extinguisher nearby.

Good luck, Henry

 

Vent lines (29, 30, 31) that "clip" onto the fuel tank.

The fittings become brittle. If the tank is full they can leak.

Check all the connections.
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I do have an extinguisher ready it's actually always in the car...

One other question, may be related.

The gas cap I have was always flimsy and the inner gasket would separate from the outer metal cover, that's until I JB-welded it about 1 year ago.

Before that and since I've always had some large pressure inside the fuel tank - so say I go for a spirited drive and stop to fuel up, the gas cap is always very hard to open and when it does there's a large pressure built up...

Should I check that the cap is vented properly? Or should it be vented better than it is now? The cap does have a hole in it (in the metal cover) but the gasket doesn't seem to have a matching hole, should it?

 

The pressure build up is not unusual Dan, especially when the car is hot. Not sure about the venting issue and the gas cap, but if something that should be aligned (hole) isn't, perhaps that's forcing some fuel down into an overflow tube and giving you that smell. I don't know if there is a simple procedure for checking the cap, but it appears at least that it's holding pressure.

Henry

 

Search my name and look for a thread I started about fuel smell. I traced mine down to a hose clamp coming off the fuel filler pipe.

Before I tightened it up, I got no hissing, pressure release upon remove of gas cap at fill up.

Now, I get an extended hiss (more than any car ever lol) and fuel smell is gone.

 

To echo what Badabing! said, there is apparently a problem when you *don't* have pressure in the tank after a drive. If it seems like there's a lot of pressure when you remove the cap perhaps the leak (assuming there is one) is on the pressure side of the fuel pump?

 

Oh I see, good point -- I did not try to open the tank today after driving it...the faint smell came close to home so I just turned it off and left it, but if opening the tank showed high pressure then it can't be before the pump and it would be after?

Although if there would be no or low pressure maybe things vented and that was the smell?

Badabing! I'll search your old thread...

 

I also had the pressure buildup in my tank and the smell was pretty intense when I parked the car in the garage.

Someone here suggested I change this 35$ valve part number 170442

After that, the smell became reduced a lot (perhaps the shop who did the work retightened the valve fittings and made sure everything was snug for all gas line connections) but the pressure buildup was completely gone. I can now open/close my gas cap freely and no pressure buildup at all.

I was also lucky because Ricambi had just 1 in stock and does not seem like they are available anymore at Ricambi.

However, if you can source the part I suggest you have it changed, did my car a whole lot of good.

 

Yeah mines like that really builds up some pressure.

 

ok so is the hiss/pressure sound when openeing the gas cap normal or not..?

 

It's extremely common and ignored by many since "they all do it" but just because it's common doesn't mean it's right.
If you're getting a big gush of pressure when opening the cap then the vent valve treedee3d mentioned is plugged up/ malfunctioning.

 

ok thanks..

I do get the hiss/pressure sound when opening the gas cap..
sometimes its more, sometimes its less and sometimes nothing..?
can that vent Valve be cleaned up etc..

that said.. I never have any fuel smells at all..

 

Is it only the vent valve that would prevent this? How about the vented gas cap? Can that be the culprit?

I know for a fact that in my car the gas cap has a tiny hole in it by design but the inner gasket doesn't seem like it does? It kept on falling off until one day when I epoxied it in there but I'm fairly certain that it does not work as a venting cap?

 

Gas caps haven't been vented for a long time.

 

Thanks -- good to know, I'll post a picture of my cap as it may be an older style?

Hi - how easy is it to change this valve on the car? I may attempt it...

 

I hate those brittle connections as I have broken a few. Are they replaceable at the tip or only the whole hose?

 

Actually I have no idea, my shop did it for me...

Doesn't seem to be too hard.

 

So since this valve seems to be NLA from everywhere would it make sense to get a one-way check valve which matches the ID of the hose that is on either side of the original?

Such as this...

ONE WAY CHECK VALVE 1/4" BLACK/WHITE HOSE BARB - pwc parts, jetski parts, riva, r&d, pwc performance

 

Super easy....screwdriver and 5 minutes.