Foul Smell in Trunk and in Cabin

[firstq]

92Q - when the car is left stading for some time (say more than half hour) stopped - the trunk and inside cabin smells something simlar to fuel - but not exactly. The smells goes away in few seconds - never does the odor come back during drive. It is only when it is sitting after having been driven....

Any pointer guys?

Thanks

[szh]

Fuel pump leak, perhaps?

Z

[Pat S]

Check fuel lines under rear of plenum. When cold, they will leak. When warm they stop leaking. Fuel smell likely being brought into cabin thru vents @ base of wind shield.

Feel around these lines when cold (running) and see if they are wet w/fuel. If so, tighten the clamps!

Pat

[szh]

I think the leak may be closer to the fuel pump and tank - the smell was in the trunk, too.

Z

[firstq]

There is no smell in the engine bay - only in the trunk, and to some extent in the cabin. Only after the car has been sitting for some time after being driven for some time.

The pump is almost new - 9 months old has only seen 8K miles - new fuel filter was installed at the same time.

I looked at the metallic fuel lines going into the pump and they look okay - I will use the wrench to retighthen it.

Anything else guys?

Thanks

[911/Q45]

I'll bet they spilled some gas when they changed the fuel pump and it ran under the tank. When the air doesn't move inside the car, it smells, but when the HVAC blows some air, it dissipates.

[firstq]

I'll bet they spilled some gas when they changed the fuel pump and it ran under the tank. When the air doesn't move inside the car, it smells, but when the HVAC blows some air, it dissipates.

The fuel pump and filter were replaced 9 months ago, why would the spill make smell now?

Looking inside the trunk, I saw one connector open (perhaps not connected to this issue) - can anyone please look at the picture and tell me what it is and where it goes?

The fuel smell is really getting bad....while taking the picture, it was really awful inside the trunk.

http://members.cox.net/azheer/q45/DCP_0594.JPG

http://members.cox.net/azheer/q45/DCP_0595.JPG

http://members.cox.net/azheer/q45/DCP_0596.JPG

http://members.cox.net/azheer/q45/DCP_0597.JPG

Thanks

[DAEDALUS]

Cell phone?

Did you remove the partition to take a look at the fittings on the fuel tank? They could be leaking, or maybe the o-ring between the tank and the pump assembly flange. It could also be a leak between the fuel filler port and the tank somewhere.

[szh]

Looking inside the trunk, I saw one connector open (perhaps not connected to this issue) - can anyone please look at the picture and tell me what it is and where it goes?

This very much looks like the coax cable and connector for the antenna for the old cell phone that Infiniti used to market. Not an issue for this problem that you are having ... I still suspect some loose connection in the fuel pump and hose lines area. Maybe the fuel tank itself is perforated (this is dangerous!).

Z

[firstq]

One important piece of info (perhaps):

There is no smell in the trunk and the cabin if the tank is full (even semi full). It is only when the tank is less than 3/4 full that the smells starts and gets progressively worst as the tank gets empty.

This has consistently been the case since this started happening.

Does this have any relevance?

Thanks

[Q451990]

Weird...

I'd say remove the back trunk cover and then see what you can find from there. You might see some sort of residue around any leaks. My guess is that they didn't replace the o-ring, or broke off one of the bolts that holds the pump assembly to the tank.

Heath

[Rex]

When the tank starts to get low, do you get the "pressure release" when you take the cap off to fill up?

If you're not getting that pssst, maybe as Heath said the o-ring wasn't replaced (and/or a bolt was broken), and as the tank level lowers and the pressure increases it blows by the old/lose o-ring.

[firstq]

The pressure is certainly there when I open up the gas tank - it was there this morning as well and the gas tank was almost dry (the low gas light was on for the last few miles).

Heath - as I have said before, the pump was changed some 15 months ago. I actually looked at the invoice and it is dated May 2002. So it has been more than 17 months now - if they did (what you are suggesting) would the problem exhibit itslef this much later?

I would definitely look into this over the weekend - seems odd that it worked flawlesly fo so long and all of a sudden the smell started appearing.

Also, if the fuel pump area is leaking, would it be pronounced inside the cabin as well (while the car is sitting turned off and no air anything going thorugh the system? Perhaps the fuel vapours can find its way into the cabin...

Thanks

[Rex]

Yes, the "vapors" could easily find their way into the cabin. The fuel pump sits atop the tank which is right under the parcel shelf behind the back seats.

When you're looking into your trunk (from behind the car) the tank sits above the trunk floor between the shock towers.

Does the invoice list the o-ring? It could be they didn't replace it and that <wasn't> an issue for well over a year. Some of the "lesser" parts that are replaced during a repair are skipped at times to save on costs, but actually create more costs down the road .

[rover3l]

This very interesting thread is very relevant to my issue of the noisy fuel pump as all the advice seems to be that I need to replace it quickly. Are there any special issues or difficulties I should be aware of in doing this job. I have picked up loud and clear that the o ring needs to be replaced.

Thinking about firstq's problem it does seem as if it is related to the pressure build up when the free volume in the tank is increased. When you have the smell have you tried relieving the pressure by unscrewing the filler cap and assessing whether the smell disappears?. If this is the case then it more or less proves that fuel vapor is finding it's way out only under conditions of pressure. Given that the fuel pump seems to be the only change to your fuel system it seems logical to suspect this as the culprit and the quality of the seal of the pump to the tank via the o ring seems plausible as a cause as others have suggested

Good luck

David

[firstq]

Well - so can someone please theroize why under only these 2 conditions the failed o-ring will cause the smell to come up:

1. Only when the gas tank is not full - the tank has to be less than 3/4 full for the smell to start to come out. --> what is the relationship b/w the failed O-ring and the volume of gas inside the tank.2. The smell is there only when the car has been sitting around for some time - never while driving and never after just stopping the car - the car has to be sitting there (even if for 5-10 minutes for the smell to start coming out) --> why is not the smell continuous?

Appreciate any feedback.

Thanks

[maxnix]

Check your activated charcoal canister that the tank vents through. I bet it's failed.

[firstq]

Check your activated charcoal canister that the tank vents through. I bet it's failed.

Max - is there an easy way to do this? I will look into the service manual as well.

Thanks

[Q451990]

I've never heard of a failure there... service manual is your best bet - I'm sure there's a process to check it. I've just never done it.

Heath

[firstq]

Guys, we are talking abut the Charcoal Carbon Cannister (Cannister Purge Conrol on page EF&EC-165 and EF & EC-226), right?

Thanks

[maxnix]

Yes, if it no longer allows venting, it could be the source of the fumes. On some cars I know they can become contaminated with gasoline if the tank is constantly over filled.__________________Brian1995 Q45 & Q45t & 2000 Q45

Discover the power of the button!

[Q451990]

[quote=" maxnix On some cars I know they can become contaminated with gasoline if the tank is constantly over filled.[/quote]

I wouldn't say that's a concern with the Q's... I've been filling mine up until it pools in the filler port since 1996. I've heard the same thing on some OBDII cars, but it doesn't seem to be an issue here.

Heath

[firstq]

I checked the Cannister solenoid with meter and open/close checks as illustrated in the service manual - everything checked out pkay (electrically).

I read thru the EC-EF page 226 and am not sure how the diagram on this page maps to the 3 lines coming into the cannister (vaccum, fuel vapor, and purge) - in other words, what is "A", "B", and "C" as stated on EC-EF page 226 mapped to (fuel vapor line, vaccum and purge).

Thanks

[firstq]

Update --> one of the fuel lines going through the plastic spacer was bumped out a little bit, pushed it back in and have not smelled gas since then (4 gas tanks).

There is a plastic spaces (or whatever it is called) that keeps the metal fule lines out of the tank in place when running from the pump into the bottom of the car (you can see it once the back cover is removed uncovering the silve gas tank).

Probably I had pushed a box or something too hard inside the trunk that dislodged one of the lines a little bit out of the spacer and this started happening. But now it is fixed.

BTW, do these fuel metal lines connect to some rubber lines close to the gas tank (as it must have bumped the metal line out of the rubber line and was causing the odor to come out - pushing it back into the plastic spacer probably sealed the join (metal line to the rubber line) again and t he smell went away)

I will be looking at where the join (metal to rubber lines in the back) is to secure the clamp making sure it is tight

Thanks

[Q451990]

I can't imagine why this would fix your problem...but who knows.

The metal fuel lines in the trunk go through the bottom of the car's body, and then go into short rubber fuel lines. These feed the long metal fuel tubes that go from the back to the front of the car. Unfortunately I know all too much about these since I had to replace the fuel tubes when my auto shipper scraped them off of "Q2" during her trip from CA.

Heath

[szh]

BTW, thanks for providing an update! It always helps when we contribute to the body of knowledge here!

Z

[Tgvince]

OK...Maybe its like the Issue i had on my SE-R. The gas lines get dry and crack near the end. In my Sentra the smell of gas would happen at odd times but never leaked. I snipped about 1/2" off the end of the supply and return line at the gas tank....Problem solved.

Terry97Q92 Classic SE-R