What Would Cause Sudden Smell of Gas Fumes?

[93gtmustang]

In the last few days I've been smeliing gas fumes when my car is running. If you get out of the car after you turn it off and then get back in a little while, you can still smell some fumes inside. By the way, I don't know if this has anything to do with it, but I just recently brought my idle down to 750 -800 rpms because it was hanging at 1500 rpms.
This is my set up.
1993 GT Mustang EFI
Timing 15 advanced
TPS Set .98
Fuel Pressure 39psi vacuum off
70mm Throttle Body
New Ford Racing GT-40 Crate Engine B-303 Bam
New 24 lb. injectors
Edelbrock Performer Intake
C&L CAI with 76mm MAF
Any help would greatly be appreciated.
Thanks

 

[jrichker]

Look for damage to the carbon canister used to vent the gas tank. There is a line that comes from the tank to a small canister on the lower passenger side of the engine compartment, just behing the roll bar. It has activated carbon in it and is connected to the intake manifold via a solenoid controlled valve.

The carbon canister vents fuel vapor into the intake manifold at cruse. This helps richen up the cruse mixture slightly. It also eliminates the gas stink when the car is closed up in the garage or other poorly ventilated place. Don’t park you car in the garage if you have a gas fired water heater, the fuel vapors are a potential explosive hazard.

Unfortunately, some uneducated people remove it in a foolish attempt to make the car faster. This isn't a viable strategy.

 

[GTSETGO]

Mine did that at first. It was the gasket on the neck of the gas tank. I don't know if it is the same thing, but just a suggestion. But, mine would also leak if I filled it above 3/4 of a tank.

 

[HISSIN50]

Jrichker's thought was my first one as well. I'd add that the discharge line vulcanizes badly where it meets the plenum. Many of us (Jrichker, IIRC, and myself, for a couple) have had to repair this part of the hose. I've had to replace and/or fix the lines on both stangs at the CC cannister as well. I like short hoses with two different sized ends.

Good luck.

 

[93gtmustang]

Thanks. I appreciate it.
I'll check it out.

 

[Darkwriter77]

Might also give the fuel injectors a look. Mine did the same thing when they started to crack and seep from old age, making tiny little pools of ultra-flammable joy upon my intake manifold. I actually drove it that way for almost a month (carrying a big fire extinguisher in the car at all times) before I scored a set of 19-pound newer-design injectors (sourced from a 4.6 T-bird) off eBay for about $75. I was going nuts trying to find it, thinking I had a split fuel line up front or something, because the fuel would evaporate off the intake manifold after just a few minutes, but the car always REEKED of gasoline after running awhile.