Canister is leaking Gas...Please Help !!!
#33
Lexus Test Driver
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I was doing some more checking on my 1JZ and I was looking at the black/blue one way check valve near the throttle body. This valve allows the engine to suck excess fuel vapor/pressure from the vapor/charcoal canister back into the throttle body to be burned off.
On my engine at some point I guess I had popped a vacuum hose off just before that checkvalve and didn't notice it, so basically the excess fuel vapor from the canister would have zero chance of being sucked back into the motor as was designed.
I haven't driven the car to test it yet, but I'm pretty sure this is why I was noticing the fuel vapor smell.
So, check your vacuum hoses, specifically the ones running from the canister back to the intake manifold, and check the one way valve operation too. You should be able to blow through it towards the throttle body, but NOT back towards the canister.
On my engine at some point I guess I had popped a vacuum hose off just before that checkvalve and didn't notice it, so basically the excess fuel vapor from the canister would have zero chance of being sucked back into the motor as was designed.
I haven't driven the car to test it yet, but I'm pretty sure this is why I was noticing the fuel vapor smell.
So, check your vacuum hoses, specifically the ones running from the canister back to the intake manifold, and check the one way valve operation too. You should be able to blow through it towards the throttle body, but NOT back towards the canister.
Last edited by RyanV; 10-16-11 at 08:00 PM.
#35
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ok so I have finally gotten around to try and check the vsv valve that is connected to the charcoal canister....one of the vacuum lines was cracked that was connected to it. This valve is super hard to get to. I basically had to raise up the driver side of the car and it can bee seen from underneath the engine. it is right above the starter and next to the vacuum tank that sits underneath the intake manifold. I'll let u guys know if this fixes the problem
#36
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I joined this forum just to pass on this information. If you are one of the people who has gas dripping out from the drain hose under your engine, or from the charcoal canister (which is what that drain hose is connected to), and IF you (or someone before you), disconnected any of the three hoses connected to the underside of your gas tank at any time, and are now experiencing this mysterious gas leak, then your problem may be something as simple as one copper washer left off of the connection that runs from the charcoal canister to the gas tank (it's on the drivers side of the gas tank, on the bottom, right above the rear axle).
I have been haunted with this exact problem for three months, since I changed out my gas tank; fuel smell in cabin, gas draining and leaving a puddle under the engine, fuel entering the charcoal canister from the return line that runs to the gas tank. I researched everything I could find, tried several things, all failed, then, low and behold, I read of someone on this forum with the same problem, and he discovered the culprit, the missing copper washer.
You can get more info from this post by dlsoul87, with pictures.
This completely fixed my problem, no gas smell, no leak, perfect. Mystery solved.
I have been haunted with this exact problem for three months, since I changed out my gas tank; fuel smell in cabin, gas draining and leaving a puddle under the engine, fuel entering the charcoal canister from the return line that runs to the gas tank. I researched everything I could find, tried several things, all failed, then, low and behold, I read of someone on this forum with the same problem, and he discovered the culprit, the missing copper washer.
You can get more info from this post by dlsoul87, with pictures.
This completely fixed my problem, no gas smell, no leak, perfect. Mystery solved.
#37
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This is exactly what fixed the issue for me...
i joined this forum just to pass on this information. If you are one of the people who has gas dripping out from the drain hose under your engine, or from the charcoal canister (which is what that drain hose is connected to), and if you (or someone before you), disconnected any of the three hoses connected to the underside of your gas tank at any time, and are now experiencing this mysterious gas leak, then your problem may be something as simple as one copper washer left off of the connection that runs from the charcoal canister to the gas tank (it's on the drivers side of the gas tank, on the bottom, right above the rear axle).
I have been haunted with this exact problem for three months, since i changed out my gas tank; fuel smell in cabin, gas draining and leaving a puddle under the engine, fuel entering the charcoal canister from the return line that runs to the gas tank. I researched everything i could find, tried several things, all failed, then, low and behold, i read of someone on this forum with the same problem, and he discovered the culprit, the missing copper washer.
You can get more info from this post by dlsoul87, with pictures.
This completely fixed my problem, no gas smell, no leak, perfect. Mystery solved.
I have been haunted with this exact problem for three months, since i changed out my gas tank; fuel smell in cabin, gas draining and leaving a puddle under the engine, fuel entering the charcoal canister from the return line that runs to the gas tank. I researched everything i could find, tried several things, all failed, then, low and behold, i read of someone on this forum with the same problem, and he discovered the culprit, the missing copper washer.
You can get more info from this post by dlsoul87, with pictures.
This completely fixed my problem, no gas smell, no leak, perfect. Mystery solved.
#38
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Hey guys just wanted to update this to point out that this also fixed my issues, but wanted to share what I went through to get here and what I experienced so that those who may find this page in the future can have an easier time.
The fitting goes as follows from bottom to top:
Union bolt: 9040112024
Washer:9043012010
Hose Fitting:7720830040 or 7726030010
Gasket: 7717130030
And washer:9043012010
I read this page and got these parts, handed them to my mechaninc and he had it done in less than an hour, HOWEVER he didn't realize that the washers go on bottom and top of this assembly, so I went from one leaky vent line, to 3 massive leaks. This caused starting problems, pressure problems, and gas just poured out of it. It also completely died on me at one point. Going back to check these fittings and putting all parts in their respective places cured everything. It starts perfect and no more leak or gas smell! I also have some extra parts I bought in the course of doing this, so if anyone needs them I will be happy to send them to you. Hope this helps!!
The fitting goes as follows from bottom to top:
Union bolt: 9040112024
Washer:9043012010
Hose Fitting:7720830040 or 7726030010
Gasket: 7717130030
And washer:9043012010
I read this page and got these parts, handed them to my mechaninc and he had it done in less than an hour, HOWEVER he didn't realize that the washers go on bottom and top of this assembly, so I went from one leaky vent line, to 3 massive leaks. This caused starting problems, pressure problems, and gas just poured out of it. It also completely died on me at one point. Going back to check these fittings and putting all parts in their respective places cured everything. It starts perfect and no more leak or gas smell! I also have some extra parts I bought in the course of doing this, so if anyone needs them I will be happy to send them to you. Hope this helps!!
#40
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True story, but not everyone who has a weird gas leak, or starting problems would think to check those specific banjo bolts. I think we're at the point now where these SC's are on their 2nd/3rd/4th owners so getting reliable info on previous work is hard. The guy I bought mine from said he went to the dealer for everything, but that turned out to not be the case at all. At any rate, more info is always better than less
#42
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Can anyone in this thread tell me where the charcoal canister assembly is located, I have a 97 SC400. Pics would help if possible, I have searched all over online and had no luck.
#43
Intermediate
Take all the lines off the canister and start the vehicle. You will see if any fuel is coming through the lines, there shouldnt be. If there is track down the line, see where its coming from, and see if its crossed. If no fuel comes through any of the lines, suspect a bad canister (full of fuel).
How much gas did you put in the car, I know if you wayyy overfill the tank fuel can go through the vapor lines into the canister.
How much gas did you put in the car, I know if you wayyy overfill the tank fuel can go through the vapor lines into the canister.
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