Help - smelling raw fuel
Thread Starter
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From: Life's tough, wear a helmet.
Help - smelling raw fuel
Patient:
1990 ZR1 #2991 (16K miles)
Symptoms:
After my commute home last night I smelled raw fuel at the back of the car while I was unloading from the hatch. I lifted the gas door but the smell was definitely not coming from there. I semi-dismissed it as my lawn mower, chain saw, and blower are all in the garage, too. I thought maybe it was from one of them or their gas cans. But later in the evening I went out to the garage and did not smell gas. So that rules out them.
I did not smell it this morning on my way out, either. Then today when I arrive at work I smell it again.
Could it be the tank or the lines back there? But if so wouldn't I smell it just about all the time? What's going on?
Diagnosis: ??
1990 ZR1 #2991 (16K miles)
Symptoms:
After my commute home last night I smelled raw fuel at the back of the car while I was unloading from the hatch. I lifted the gas door but the smell was definitely not coming from there. I semi-dismissed it as my lawn mower, chain saw, and blower are all in the garage, too. I thought maybe it was from one of them or their gas cans. But later in the evening I went out to the garage and did not smell gas. So that rules out them.
I did not smell it this morning on my way out, either. Then today when I arrive at work I smell it again.
Could it be the tank or the lines back there? But if so wouldn't I smell it just about all the time? What's going on?
Diagnosis: ??
Race Director
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From: Hillsborough NH
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Re: Help - smelling raw fuel (Scoob)
with a 90 having such low miles, its possible that a hose has cracked, or at least a gasket has degraded.
With my thinking, you wouldn't get a smell after it sitting, because there isn't any pressure on the system... :)
Just my guess.
With my thinking, you wouldn't get a smell after it sitting, because there isn't any pressure on the system... :)
Just my guess.
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St. Jude Donor '03-'04
Cruise-In 1-2-3-4-5 Veteran
Re: Help - smelling raw fuel (Mervz)
The soft fuel line going from the tank to the vapor canister has a one-way valve in it that can fail or clog. Also, the vapor canister itself can just crack and start leaking fumes. Think about replacing the soft fuel lines and/or the vapor canister. The canister is mounted on a bracket under the passenger side rear bumper, behind and below the tail-lamps. There's a metal shield that partially hides it from view.
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From: Athens AL
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Re: Help - smelling raw fuel (Scoob)
Normally id say you might have a leak in the fuel tank/lines or leaky injectors, but the ZR1 is its own animal, ask those guys.
[Modified by vader86, 9:09 PM 10/2/2002]
[Modified by vader86, 9:09 PM 10/2/2002]
Thread Starter
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From: Life's tough, wear a helmet.
Re: Help - smelling raw fuel (Matt Black)
The soft fuel line going from the tank to the vapor canister has a one-way valve in it that can fail or clog. Also, the vapor canister itself can just crack and start leaking fumes. Think about replacing the soft fuel lines and/or the vapor canister. The canister is mounted on a bracket under the passenger side rear bumper, behind and below the tail-lamps. There's a metal shield that partially hides it from view.
Thread Starter
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From: Life's tough, wear a helmet.
Re: Help - smelling raw fuel (vader86)
Normally id say you might have a leak in the fuel tank/lines or leaky injectors, but the ZR1 is its own animal, ask those guys.
I'm 99% sure that this is not ZR1 related so much as basic C4 related.
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St. Jude Donor '03-'04
Cruise-In 1-2-3-4-5 Veteran
Re: Help - smelling raw fuel (Scoob)
Yes, there is pressure in the lines for a long time after the car is off, unless we have leaking injectors.
The fuel system stores the built-up tank vapors in the canister after shut-down, and the management system pulls the fuel vapor out of the canister as the first thing it does on startup. If the smell is present really heavily just after engine start, that would be the line or the canister. A heavy smell after shutdown, though...that sounds more like a liquid-fuel leak!
I will go read my fuel-system section of the service manual again...
The fuel system stores the built-up tank vapors in the canister after shut-down, and the management system pulls the fuel vapor out of the canister as the first thing it does on startup. If the smell is present really heavily just after engine start, that would be the line or the canister. A heavy smell after shutdown, though...that sounds more like a liquid-fuel leak!
I will go read my fuel-system section of the service manual again...
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Thread Starter
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From: Life's tough, wear a helmet.
Re: Help - smelling raw fuel (Matt Black)
Matt - I can't say if the smell is there at startup since I'm inside the car at the time. If I just went out and turned the key to activate the pumps (not starting the motor) do you think I'd smell it?
I don't think it's a liquid leak as the odor goes away fairly quickly after I park.
I don't think it's a liquid leak as the odor goes away fairly quickly after I park.
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Thread Starter
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From: Life's tough, wear a helmet.
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St. Jude Donor '03-'04
Cruise-In 1-2-3-4-5 Veteran
Re: Help - smelling raw fuel (Scoob)
I like to start the day with the windows rolled down, weather permitting. When I had my fuel odor, the reason I noticed it was morning technique. Windows down, shift into reverse, and back up *though* my own cloud of gasoline vapor. That's when I noticed it - backing through the vapor I was releasing on startup.
But a fuel vapor smell, well, I was rear-ended two weeks after I bought my car. Scratched the bumper cover, and cracked the vapor canister. But I replaced all the soft fuel lines as well as the canister. The segment with the one-way valve was the most expensive, and I think it was $36.
But a fuel vapor smell, well, I was rear-ended two weeks after I bought my car. Scratched the bumper cover, and cracked the vapor canister. But I replaced all the soft fuel lines as well as the canister. The segment with the one-way valve was the most expensive, and I think it was $36.
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From: Life's tough, wear a helmet.
Re: Help - smelling raw fuel (Matt Black)
Thanks for all your help, Matt.
Hey, with the key turned to "run" but the motor not started this circled part buzzes at me every 10 seconds or so. Is this a fuel system related part and could it be buzzing as a symptom of something wrong in the fuel system somewhere? This is on the right corner, just in front of the coolant overflow bottle. I don't recall having something like this on my old '89.
Hey, with the key turned to "run" but the motor not started this circled part buzzes at me every 10 seconds or so. Is this a fuel system related part and could it be buzzing as a symptom of something wrong in the fuel system somewhere? This is on the right corner, just in front of the coolant overflow bottle. I don't recall having something like this on my old '89.
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Joined: Jan 2002
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From: Madison Mississippi
Re: Help - smelling raw fuel (Scoob)
I had a mysterious "fuel smell" on my '96. After numerous trips to the dealer under warranty, they came with zilch. It usually happened during high temps, but it was more prevalent in the morning... Finally traded the car, but never found the source of the problem.
Sorry for not being any help, but maybe you can solve yours... :D
:cheers: :cheers:
Sorry for not being any help, but maybe you can solve yours... :D
:cheers: :cheers:
Instructor
Joined: Dec 1999
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Re: Help - smelling raw fuel (Scoob)
Scoob, I don't have a ZR-1, but I had a fuel smell too. Odor was quite strong and I was sure it would have been a liquid leak somewhere... Finally found it in the fuel vapor lines. Because they are not pressurized like the main fuel lines, it seems that GM did not make them in one piece. They are joined or spliced together in the tunnel just inboard of the LR wheel. I replaced the rubber lines (all of 2 inches long) and smell was gone. I guess because the lines were so close to the driver side it was soo strong.... Take a look..........
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From: Florida
Re: Help - smelling raw fuel (fundriving)
Scoob, I don't have a ZR-1, but I had a fuel smell too. Odor was quite strong and I was sure it would have been a liquid leak somewhere... Finally found it in the fuel vapor lines. Because they are not pressurized like the main fuel lines, it seems that GM did not make them in one piece. They are joined or spliced together in the tunnel just inboard of the LR wheel. I replaced the rubber lines (all of 2 inches long) and smell was gone. I guess because the lines were so close to the driver side it was soo strong.... Take a look..........
