Fuel (gas) odor in my '90

[RLDaily]

OK girls I'm on the horns of a delima, and here's the deal.
My car ('90-L98-no mods) is giving off a fuel odor when I drive. Here are the conditions:

Parked, at idle, no odor, no signs of leakage or moisture areound fuel system components

30-40mph or so, driver widow down, fuel odor. Inspection shows no signs of leaks or seeps in system components

30-40mph or so, driver windo up, no odor and no signs of seeps or leaks in system

50-60mph or over, driver window down or up, no odor, inspection shows no seeps or leaks in system

The engine in all parameters runs smooth and the cars doesn't leave any traces of seepage when I park it...It's dry underneath and no evidence of fuel staining.

Questions...
1: Could exhaust fumes be coming into the car at lower speeds? (Of course I'm smelling raw fuel and not exhaust)

2: Could there be something I'm missing?

3: Every car has it's eccentricities so is there something about the C4 or the '90 in particular with this issue?

I'm not a novice with twisting wrenches (I built some killer '65 GTO's and a monster 68 AMX many years ago among other things and we won't even discuss my A&P) but I am kinda new with the C4 stuff.

So what do you guys think? (I'm gonna be asking this same thing in a couple of other forums because it is driving me crazy trying to track it down

Thanks....Randy

 

[John Robinson]

Evap

http://i285.photobucket.com/albums/ll72/John-68/EVAP0001-1.jpg

This a copy of a section that discusses the EVAP system. I hope this will point you in the right direction with your fuel vapor smell

That picture may be too small to read so hear is the pertinent info. The EVAP canister on 84 through 90 C4 was in the left front of the car. There are several possibilities for the smell but basically it comes down to something is leaking.

 

[air1jpg]

I am no Mr. Goodwrench, but the only thing I can think of is maybe your injectors are leaking or maybe you are running a bit rich.

 

[boomdriver]

I'll throw my bet in with John.

the EVAP system takes fuel vapors and recirculates then back to the tank. This goes thru a charcoal canister up in the nose by the headlite drivers side. The bottom of the canister has a vent line that just ends right there. I am not sure of the why, how or what to do, but that can lead to some random fuel smell with no evidence of a leak.

Gasoline being what it is, be vigilent and look at everything. I once had a fuel smell that turned out to be a leak in a steel fuel line that was spraying directly onto the exhaust shield on the passenger side....I smelled it for days and only spotted it by accident. The fan would disperse the fumes so that I could not tell where they originated. I saw the leak.

 

[T.M.808]

yep. 3 votes for the evap. Pop you're hood,start the car and see if the smell is coming from the canister behind the headlight.

 

[Nick90vetteguy]

I got a 90 myself, I took off my mufflers and cleaned out my air injection, mine to gives off alot of fumes maybe a burnt gasket? or bad exhaust valve?

 

[mailmaninvette]

On my 87 I found that the EVAP line had a short piece of rubber line
where the frame kicks up on the drivers side. I found the leak by taking
off the EVAP line at the canister and the fuel pump,plugged one end and
a little air pressure in the other end.