Smell gas when I roll down the windows....

guys72Mach1

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So I can drive around all day long with the windows up and not smell a thing, but if I crack my windows, with 10 seconds I get a fresh fuel wiff that fills the passenger compartment.

If I roll the windows down all the way, it flow enough air to take it out.

There are no fuel leaks, so it's definetly coming from the trunk.

All my fuel lines and filler neck line are new, so nothing getting out there.

When I pop the trunk, it's doesn't smell like gas.

So only when I crack or roll a window down a little, when I'm moving it draws the fumes in?

Anyone else have this or is it just me?

 

sm3570

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Hell, don't light a match!

Are you sure it's not coming from the engine compartment? Is the engine running rich? Mine does that right now because I haven't upgraded the ignition.

 

guys72Mach1

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Hell, don't light a match!

Are you sure it's not coming from the engine compartment? Is the engine running rich? Mine does that right now because I haven't upgraded the ignition.
Nope..running like a top. This is raw fuel fumes, right from the trunk. It's like a vacuum inside the car and as soon as a window is rolled down it's pulled up to the passener compartement.

 

Tnfastbk

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Gas cap leaking? Where is your vent ran too?

 

Jeff73Mach1

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I get the exhaust smell with the window down a certain amount. You can actually feel hot air sort of swirl into the car. It is even worse if you sit in the back seat. Window all the way down and it doesn't draw it in. I've checked over everywhere and it is definitely exhaust, not raw fuel. I believe it is a aerodynamic issue.

 

edd

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does it have pop open gas cap ,mine did the same and it was the seal on the cap

 

MotoArts

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Back in the '80's I had a Datsun 240Z with a similar problem.

I had dual exhaust like a Jaguar with tailpipes coming up under the differential and exiting up near the bumper. Exhaust fumes would enter in the same fashion, depending on how the windows were opened.

I blamed it on a dry rear decklid seal, but certainly could have been taillight seals, etc.

Aerodynamics and air pressure, yes...

 

guys72Mach1

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does it have pop open gas cap ,mine did the same and it was the seal on the cap
It's the pop open cap, but the NASA style with the twist cap underneath.



Gas cap leaking? Where is your vent ran too?
Whatchu talkin bout Willis???? What vent?

 
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OMS

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There is a vent on top of the gas tank - it goes to the charcoal canister, then to air cleaner

when you open the twist cap do you ever hear pressure being released, if so vent is plugged

Pull your door jamb vents look at the rubber flaps in the back - could be drawing air in from the 1/4 panels

 

guys72Mach1

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There is a vent on top of the gas tank - it goes to the charcoal canister, then to air cleaner

when you open the twist cap do you ever hear pressure being released, if so vent is plugged

Pull your door jamb vents look at the rubber flaps in the back - could be drawing air in from the 1/4 panels
Charcoal canister and stock air cleaner is long gone. I'll check the tank for the vent line though and see where it end at.

I don't hear anything when I take the cap off.

I'll check the flappers. thanks for the possible solutions.

 

midlife

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Cracking the windows open just a bit causes a slight vacuum in the car when moving: the infamous Bernoulli effect. That vacuum is taking fumes from your trunk area and passing it through the passenger compartment and out the window.

As well as the vent hole on the tank, also check the tube from the rear of the car into the tank. There's a rubber joint that can crack when it is old.

 

goodnigh

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Mine smells like gas as well.

It is a perfume that attracts the Ladies :cool:

We installed a non-stock air cleaner and there is

no place to connect the blue cannister to the air

cleaner. Need to work on that.

mike

HPIM3172.JPG

 
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If it smells like gas I doubt it is the exhaust. More than likely the charcoal canister vent to the gas tank. I do not have mine hooked up to the air cleaner on my vert. I think I put a piece of tape over it. I do not smell so I would never know if I have a leak or not. Sinus surgery took my smeller out and taste very little.

 
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