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Fuel Odor 2004 CRV

Have taken my 2004 CRV to the dealer 5 times over the last 6 months because I smell gas after turning the vehicle off. I mostly smell it when I get out of the car. The smell is coming from the gas tank area, but there are no visible leaks. The dealer has smoked it, replaced the gas cap, replaced a fuel sensor, done pressure tests which were negative, and now is recommending replacing the entire fuel sending system, which I believe is the fuel pump and something else for $1200. I consulted a mechanic friend who helped me take off the cover under the back seat which exposes the top of the tank and we put soapy water around the top of the tank where the fuel pump attaches while pumping air into the sealed off tank. We were hoping that it might just be a bad gasket but there were no visible air bubbles. Now another mechanic is suggesting that I have a small leak in the seams of my gas tank and wants to drop the tank to see if there are signs of leakage. Seems like I keep spending more and more money on guesses. Anybody else want to take a guess??? I’m seriously thinking of getting rid of this car as I get headaches after driving for more than 20 minutes, not to mention the headache I have from having this problem drag on…

Unfortunately this does just require having someone you trust get to the bottom of it. Can you stick with your mechanic friend?

The only thing I can think to ask that you didn’t mention is whether or not anyone thoroughly checked the evaporation system lines - unless that is what the dealer smoked. These carry the gas fumes from the tank, down the length of the car, and to the engine to be burned. They’re just plastic or rubber and often do have problems. If one of those was broken or split, it would be sending gas fumes out.

Thanks for responding cigroller. Unfortunately, my one friend isn’t really a mechanic, just a tinkerer, and didn’t really have any other ideas. I’m guessing the evap system lines you mentioned are part of what the dealer is recommending I replace for $600. Would that be considered part of the “fuel sending system?” They said they couldn’t test that, but just had to replace it. What do you think of the gas tank leak idea given by the other non-honda mechanic (he’s a real mechanic)? The smell is strongest just above the gas tank.

There are pieces that go from where you put in the gas, and the tank itself. Throwing big bucks at it is not the way to go. Just for kicks change the gas filter! It may be a failing connection there. Being as how "I’m seriously thinking of getting rid of this car as I get headaches after driving for more than 20 minutes, I think you are looking at the wrong end of the car, as any fumes in the rear should not enter the cabin.

Find a mechanic that has something like this & knows what to do with it: http://www.ridgid.com/Tools/Gas-Sniffer-Index/index.htm

I’m not sure what they would mean by the “fuel sending system” unless they just mean replacing the fuel pump & all fuel lines. That’s kind of like hunting a mouse with an elephant gun, and just indicates that they’re not serious about finding your problem.

Can you clarify whether you can smell this inside of the car or not? And when you say its strongest just above the gas tank, do you mean just above where you fill it up? So just above the gas cap?

@cigroller- I don’t actually smell gas in the car while I am driving. But I do seem to consistently get headaches after driving distance, so I suspect that I am inhaling some kind of fumes. Sometimes after I turn the car off, I can smell it a bit at the rear of the car. I think the vapor/fumes are being blown back as I drive. When my friend and I pulled up the access panel to the fuel pump (which Honda calls the fuel sending unit), the smell was very strong under the panel, which is the top of the fuel tank. The back seat sits on top of this panel. There is not a strong smell where the gas cap is. It’s more by the wheel well next to the gas tank and when I walk behind the car as I get out.

If you are getting headaches, then maybe take a portable CO detector in the car and makes sure it is not CO you are being exposed too.

Checking for fuel leaks around the gas tank/fuel pump should not be very difficult.

I had a classic Mercedes which developed a persistent gas smell. Turned out the gas filler line at the opening to the tank was slightly bent, which pushed the gas cap outward just enough to leak fumes. Our mechanic had a device which sensed fuel vapor and this localized the problem.

Given all of that info I’m going to say that the car isn’t safe to drive right now. You do need a mechanic with a fuel vapor sniffer. I’d look for that before I allowed anyone to go on an open-ended fishing expedition.

When you remove the gas cap to fill up with gas, does anything notable happen? E.g., do you always get a pretty big whoosh of fumes out of the tank? Gas is volatile & evaporates at a high rate. The fumes are captured to be burned rather than vented. If the evap system is clogged your whole tank & vapor lines can be getting over pressurized. This could happen in such a way that it wouldn’t necessarily turn on the check engine light.

But since you haven’t said and it hasn’t been asked, is there a check engine light on?

@cigroller – no big whoosh when I open gas cap. I have asked Honda about that and they say it’s normal. But I do think I got more of a whoosh before this problem started, which makes me think the vapor is leaking out somewhere else, even though they say they ran pressure tests and there was no drop in pressure. No check engine light either, which Honda claims would come on if there was dangerous leakage. A few years ago, the evap canister vent hose was leaking and I smelled gas, but the light did come on and they fixed the problem. I will try to find someone with a vapor sniffer, but I live in a pretty rural place, so not sure if anyone has one. Thanks for your help.

You have under the vehicle and evsporative system and charcoal canister that includes lines, a purge valve, a purge valve solenoid, and other assembly and mechanical components. It looks very much like the “exploded view” drawing in the attached link.

http://www.hondasuv.com/members/showthread.php?t=56320

Any number of components could be suspect, however I’d first suspect a saturated charcoal canister, perhaps a malfunctioning purge valve or solenoid not allowing gas fumes to be purged from the canister.

Have you had the Check Engine Light come on?
Topping off the tank after the handle shuts off can get gas in the canister. Do you do this?

The smoke test only checks for leaks, and not necessarily in the whole system. It’s a good test, but you’ll need to go deeper to solve the problem. A shop could use a sniffer (hydrocarbon detector), but without one and without a malfunction code or even a lift, it might be tough to get to the bottom of the problem. It might be worth the $100 (typical) diagnostic fee to have a shop look at it.

My parents had a similar problem with their VW Jetta wagon. The dealer smoke tested the system and found that mice had chewed through one of the rubber/plastic hoses that carry gas vapor from the tank to the charcoal canister in the engine compartment. They had to drop the gas tank and replace the hose.