This little discussed plastic tube, hidden from quick visual inspection, can be one of the chief overlooked sources for gas fumes in early Z cars.
For reasons unknown, Nissan decided to insert this small plastic tube between upper plastic gas filler tube and rubber vapor recovery hose that allows gas fumes or gas overfill to be recovered back to the gas vapor recover tank mounted behind the passenger side interior rear quarter panel.
Quite often this yellow plastic connector piece is hidden from view inside rubber hose ends. I have most often observed cracks to be on on the backside of observable area of tube and hence, not easily seen unless vapor tank is first unbolted from body and a closer inspection made with vapor tank pulled away from body cavity.
If, in attempt to stop the infamous and unhealthy gas fumes from occurring after filling up your gas tank, you’ve installed new hatch and tail light seals and you still have the fumes, remove the passenger side rear quarter interior panel, unscrew the clamps on the upper rubber hose connecting into the upper area of your vapor tank and very carefully pull back one end of the hose enough to see a bit of the the light yellow colored plastic tube inside the 2 rubber hose ends. Look for any sign of visible cracks and sniff the area with your nose. If cracks are visible or fumes detected, you will need to continue to very carefully ease off the rubber hose ends in order to remove the plastic tube inside. Once removed you will be able to do a thorough inspection for any damage.
Caution: If not yet cracked or if a few small cracks in tube are present, too careless or forceful efforts to pull rubber hose ends away from upper filler tube and/or rubber vapor recovery hose coming from gas tank vent can lead to damage or further rupture of cracks in aged plastic tube, so proceed with utmost care.
Eric Neyerlin – owner of ZPARTS.COM