Car smells of gas vapor

[Torxx]

My garage smells like fuel vapor (from my fiat). The trunk also smells of fuel vapor. No visible signs of leakage anywhere. Not sure if odor emits from engine bay or not? Engine and gas tank have been pulled cleaned and painted. New hoses, etc, new carb. All emission equip. removed. Is this common with these cars? Any suggestions would be appreciated.

[jfrawley]

Get under the drivers side rear and take a whif of your rubber filler hose. I bet thats where it's coming from; it sure is on mine. I have a new hose also, but no help. I think the gas sitting in it causes it to smell. There are some suggestions in other posts, so do a search. I'm going to try a couple of different things this weekend, and I'll check back if I have any luck.

[jimincalif]

My trunk is the same. So far I've:

1. removed the gas tank, had it cleaned out and sealed
2. replaced the rubber fuel line to the fuel pump
3. replace the rubber return line from under the car to the tank
4. replaced the fuel filler hose
5. replace the fuel overflow hose
6. replaced all the vent hoses
7 reseated the fuel gauge pickup with gasket sealant.

All that is left is the liquid/vapor separator - do these things leak fumes? I don't see how fumes could get into the trunk from under the car since gas vapor is heavier than air. I'm going to replace the hose clamps on the vent hoses with FI band-style clamps, but otherwise I'm out of ideas. If you solve it, please post back. Good luck.

[ventura ace]

Torxx,
What year is your car, and was it equipped with a charcoal cannister (engine compartment), and pressure relief valve (trunk area near the gas tank)? These items are important for controlling the gas fumes.
1) If you cap off the line to the charcoal cannister, the trapped gas fumes can build up pressure, and once the pressure overcomes the cracking pressure of the pressure relief valve, the fumes will be vented out into the trunk area.
2) If you remove the charcoal cannister, and leave the line open (the line from the gas tank to the cannister), excess fumes will vent into the engine bay area.

The relief valve and the charcoal cannister are important for allowing your fuel tank to breathe properly, and for capturing the fumes from the fuel. Check to see if they are functioning properly.

Alvon

[Torxx]

Alvon, mine is a 79. Charcoal filter was removed, and I am unfamiliar with the relief valve. I don't remember removing any equip from the trunk area. It's been a while, but, it seems like I had a fuel smell when all the emissions equip was on??
How do I ID the relief valve and how would I install the charcoal filter?? I now have a new carb and a 1800 intake, if that matters?

Thanks

I double checked, and the car had the gas smell issue prior to removing the charcoal filter, not to say that that system was working properly.

[ventura ace]

I'm not familiar with your '79, but my manual shows that the vapor recovery line from the tank goes to the fuel/vapor separater, then to a 2-way valve (probably in the trunk, and near the gas tank), then up to the engine bay where the charcoal filter is. The charcoal filter picks up these fumes and the waste fumes from the carburetor, then sends them back carburetor (probably a vacuum port). Maybe someone else with a '79 will chime in.

Alvon

[jimincalif]

The two way valve on my 1980 is under the car, above the rear axle, aft of the fuel pump. Hose from the fuel vapor separator exits the trunk in the same area as the fuel supply/return lines from the tank. then the two way valve, then another length of hose before it connects to steel tubing for the run to the engine compartment.

Jim

[laura79]

i have the same problem with my '85 pinifarina.My car is an european version, without a charcoal cannister and i can't see any valve in the trunk area. the smell is stronger when i brake and then i restart from a stop. I think that the problem is the gas cap, wich is lock and vent the tank. I tried another gas cap, wich was unlock and the car didn't smell but when i opened it there was a lot of pressure in the tank so i put my old gas cap. Now i don't know how can i do to stop the odor. any ideas?thanks.

[Torxx]

I may have vapor fumes form more than one source, but, when I crawl underneath the filler elbow and smell, there is an obvious fuel odor. I will concentrate on that for now. It sounds like some have replaced the elbow at the bottom with no improvements?? Not sure where to start. i am currently experimenting with leaving the gas cap a bit loose, as someone mentioned in a previous post, to relieve pressure in the tank.

[SpiderJim]

i have the same problem with my '85 pinifarina.My car is an european version, without a charcoal cannister and i can't see any valve in the trunk area. the smell is stronger when i brake and then i restart from a stop. I think that the problem is the gas cap, wich is lock and vent the tank. I tried another gas cap, wich was unlock and the car didn't smell but when i opened it there was a lot of pressure in the tank so i put my old gas cap. Now i don't know how can i do to stop the odor. any ideas?thanks.

I may be mistaken but with an Fi car you do usually have pressure in the tank? All my other makes of Fi cars are pressured tanks and my 81 Spider also. In fact the Spider holds pressure for quite some time after the car as been sitting.

[laura79]

Thank you for your answer. i don't know if pressure is normal in FI fiat but i think in mine is too much because if i take off the cap after it's run and the tank is half full the fuel goes up and flows out. And when it's a warm day if i turn on the car i can hear a bang like there are too much fuel's vapors. I hope you can understand, i'm sorry but my english isn't very good.

[jimincalif]

Yesterday I replaced the hose clamps on all the vent hoses in the trunk with FI-style band clamps. I also took out the fuel vapor separator and verified that vapor could flow thru it. Next I blew into the vent line that exits the trunk and goes to the charcoal canister. At first I could not blow thru it at all, so I removed the two way valve and blew thru it. It takes a certain amount of pressure to release, then vapor will flow thru it. So it is a matter of making sure the tank and various hoses will hold more pressure than the release point for the two-way valve. I Sprayed some PB Blaster into it and exercised it, it seemed to work better then. Reinstalled it and could blow thru from the trunk, so reconnected the hose to the fuel vapor separator.

Checked the trunk today and it definitely seems better. I think there is a little residual smell in the mat, but definitely made some progress.