Smell raw fuel when car is parked - time for new gas cap?
#1
Smell raw fuel when car is parked - time for new gas cap?
13b 6-port
Dellorto 48dh
RB full exhaust
low press. stock gsl fuel pump
Car has been parked in the garage for about a month now, and when i'm down on the ground doing work on her I'm smelling raw gas. Sniffing around the car, its coming from the filler / cap area.
Carb smells fine. Great actually *huff puff* mmmmmm
Exhaust smells like exhaust.
Gas lines are dry
FPR is dry
Engine bay smells like an engine bay.
Gas cap smells like raw fuel.
I noticed theres a little tiny hole drilled in the center of the cap - so i figured that might be it. I pulled the cap, stuffed a rag in there, and put some silicone over the hole. I let it dry for a day.
Interestingly, while the cap was off and the tank plugged with a rag, the smell went away! I put the re-sealed gas cap back on and it smells again!
So i'm thinking - bad gas cap gasket? I think i'll be ordering a new Mazdatrix gas cap for good measure, but why the heck was there a hole in the gas cap - i thought it was supposed to be sealed?? It looks exactly like all other OEM gas caps i've seen otherwise..
Dellorto 48dh
RB full exhaust
low press. stock gsl fuel pump
Car has been parked in the garage for about a month now, and when i'm down on the ground doing work on her I'm smelling raw gas. Sniffing around the car, its coming from the filler / cap area.
Carb smells fine. Great actually *huff puff* mmmmmm
Exhaust smells like exhaust.
Gas lines are dry
FPR is dry
Engine bay smells like an engine bay.
Gas cap smells like raw fuel.
I noticed theres a little tiny hole drilled in the center of the cap - so i figured that might be it. I pulled the cap, stuffed a rag in there, and put some silicone over the hole. I let it dry for a day.
Interestingly, while the cap was off and the tank plugged with a rag, the smell went away! I put the re-sealed gas cap back on and it smells again!
So i'm thinking - bad gas cap gasket? I think i'll be ordering a new Mazdatrix gas cap for good measure, but why the heck was there a hole in the gas cap - i thought it was supposed to be sealed?? It looks exactly like all other OEM gas caps i've seen otherwise..
#2
Waffles - hmmm good
iTrader: (1)
Probably a PO did that because the vent system was plugged on the tank. Make sure your
vent system works or you will be trading a smell for another issue.
See when the vent doesn't vent, gas can't be sucked out after awhile and you get a lean stall.
Can be very frustrating to track down but now you've been warned!
vent system works or you will be trading a smell for another issue.
See when the vent doesn't vent, gas can't be sucked out after awhile and you get a lean stall.
Can be very frustrating to track down but now you've been warned!
#3
Well its a GSL-SE, not sure if that makes a diff, but i know it has a sealed tank / cap.
I put a new cap on there - no longer smell gas. Seemed legit, so i road tripped it this weekend, put on about 200 miles, and she ran great!
By "venting system" do you mean the charcoal canister?
I put a new cap on there - no longer smell gas. Seemed legit, so i road tripped it this weekend, put on about 200 miles, and she ran great!
By "venting system" do you mean the charcoal canister?
#4
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#5
Waffles - hmmm good
iTrader: (1)
The symptom to watch for when the venting is screwed up is pressure build up on a hot day or
a vacuum hiss when the cap is removed after cruising for a long ways. Sounds like your good to
go for now.
a vacuum hiss when the cap is removed after cruising for a long ways. Sounds like your good to
go for now.
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#8
Yeah, shutup kid.
Yeah, that's why there's a charcoal canister. The system is sealed, the canister connects to the fuel tank and a vacuum line to draw the vapors into the engine while running. The canister also has a vent that allows it to release pressure on a hot day. The charcoal neutralizes the gas smell so you don't notice it.
#9
Yeah, that's why there's a charcoal canister. The system is sealed, the canister connects to the fuel tank and a vacuum line to draw the vapors into the engine while running. The canister also has a vent that allows it to release pressure on a hot day. The charcoal neutralizes the gas smell so you don't notice it.
#10
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So if when you take the gas cap off after driving for a few miles and a fare amount of air comes out would that mean my charcoal canister is stopped up and not venting properly?
#13
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well don't forget that the fuel pump is removing liquid from the tank and not replacing it, so there can be a small about of low pressure on in the tank, after driving. i do mean small too
#15
Always Wanting to Learn
iTrader: (49)
Well, glad I popped into this thread! Just learned a lot from you guys about the equal pressure necessary in the fuel system.
Glad to hear the cap solved the issue too, nice relief for your car ioTus. I'll look for that chrome trim piece tomorrow morning I promise!
Glad to hear the cap solved the issue too, nice relief for your car ioTus. I'll look for that chrome trim piece tomorrow morning I promise!
#16
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kinda of an old thread, but i'm having these issues... extreme pressure under the fuel cap, and fuel smell. anyone have pics of the line to replace on the canister? and what's a reliable cap to track down?
#17
Well I suggest just getting the OE replacement gas cap from Mazda, which you can get through a dealer, Atkins Rotary, or Mazdatrix. The cheapo caps from O'Reiley's work well too, but the gasket isnt as high quality and I doubt will last more than a year or so.
The line that I replaced on my canister was just the skinny vacuum line that jumps to the hardline. I'm still getting massive pressure build up - so I'm fairly certain my charcoal canister is clogged.
The line that I replaced on my canister was just the skinny vacuum line that jumps to the hardline. I'm still getting massive pressure build up - so I'm fairly certain my charcoal canister is clogged.
#19
Wait so how do you fix this if there is no charcoal canister? Apparently i have this problem too but my cars pretty stripped. Should i put a vacuum line to the intake manifold?
#20
Skinny line goes to tank - thick line goes to intake mani.
You can test if the lines are clogged by blowing into them.
#21
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Almost thinking I should dig into my system now.
I never really notice pressure, but I do remember being low on fuel last week, and when I filled up I got a good whoosh from the cap.
So hot day/long drive/low fuel = normal wooshing?
I never really notice pressure, but I do remember being low on fuel last week, and when I filled up I got a good whoosh from the cap.
So hot day/long drive/low fuel = normal wooshing?
#22
In = long drive consumes fuel and lowers gas level in tank and therefore less pressure. Opening tank normalizes pressure by sucking in. Seems to me not as big of a deal as:
Out = ambient temperature increases, pressure increases as gas fumes build up (not venting), pop the cap and it normalizes by blowin gas atcha.
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