Strong Gas Vapor Smell rear passenger side

Parkerbot · #1 07-15-2010, 03:52 PM

I have an 04 Nissan X 6cyl N/A 2WD. I recently did the intake mod, changed plugs and fuel filter. I looked underneath the X and couldn't see a leak but could smell a strong odor of vaporized gasoline. I found a part (not sure what it was) that appeared to venting vapors next to the spare tire on the right side (photo below). My questions are...what is it...and why would it be venting gas vapors when the engine is running? BTW 3/4 of a tank atm...filled up this morning before we took a trip to the Diamond Mine State Park in AR.

dejablue · #2 07-15-2010, 04:38 PM

it could be plugged up . how is it when you fill it up with gas at the pump (slow to fill)

Parkerbot · #3 07-15-2010, 04:39 PM

So nissan says its the Water Seperator and its part of the EVAP system...can anyone tell me if the failure of this part would cause it to vent gas vapors or could it be just a symptom of another part in the EVAP system failing? The lead mechs at Nissan had left for the day otherwise I would have asked one of them. Thanks in advance guys.

dejablue · #4 07-15-2010, 05:00 PM

yes buy the part install 15 mins .on a 1-10 a 2 only hand tools no special tools .

Parkerbot · #5 07-15-2010, 05:43 PM

I planned to...I mean its only a $14 part so cheap enough to throw money at it...reason I ask about other parts causing it, is that I'm about 1k miles from home on leave and I gotta be back the end of next week...part has to be ordered and will be in next Tues...not a whole lot of wiggle room. May just try to extend my leave just in case...

Parkerbot · #6 07-17-2010, 11:36 AM

Got the part in...same results...fuel vapors still escapting through the water separator. Thinking the EVAP canister may be clogged or the vent control valve has had it. Looks like I'll be spending a few more days here...glad it's still under an extended warranty.

fishx · #7 07-17-2010, 03:22 PM

I had the same problem. Turned out the fuel tank had rusted out around the sending unit connection allowing fuel vapors to escape.

There was a TSB about this for 1st gen Xterras in the Northeast.
Not sure if you're covered under that but it might be worth taking it to the dealer and getting it checked.

I got a new fuel tank and sending unit at no cost to me due to this.

Parkerbot · #8 07-18-2010, 10:44 PM

The gas tank looks in good repair...and the vapors are for sure coming from the EVAP system. I could see gas vapors condensing in the opening of the water separator. Gonna drop it off at the dealer here tomorrow. Hopefully the extended warranty covers an EVAP system failure.

lostcanuck · #9 07-18-2010, 11:28 PM

i've had the same smell issue this past week, what part exactly ? pic ?

Parkerbot · #10 07-18-2010, 11:45 PM

The smell is coming from the circular black part (pic above) called a water separator. It's located on the rear passenger side in between the leaf spring and spare tire...has two hoses coming out of it one on the side and on from the top attached to a 90 degree elbow. It only vents when the engine is running. Hanes Manual says fuel vapor smell can be caused by a clogged EVAP canister or Vent Control Valve (only thing I saw thats related to the EVAP system). I'll know more after the stealership takes a look at it tomorrow.

***edit***Its connected by a plastic clip to an L-Bracket attached to the rail.