Car smells like gasoline from the outside, ideas?

[a.bentonab]

For about the past week or so I've noticed a gasoline smell in the garage when my car is parked in it. I removed the other car and the gas can for the mower so I know it's coming from the car. There are no drip spots on the concrete nor any wet spots on the engine or underside if the car. Smell seems strongest under the car on either side of the gas tank. No check engine light or problems with the functioning of the car. No smell from around the gas cap or from engine compartment. Only stuff I've done with the car is replaced the valve cover gasket about a year ago. Fuel lines appear intact without leaks but I haven't run the car while watching them. No visible surface rust or damage anywhere.

my list of possible causes so far includes a problem with the charcoal vapor canister or a hole in the top of the gas tank from rust or something. Any ideas as far as other things I could consider or tips to diagnose/ fix these? I'll take anything I can get as the majority of my wrenching skills I obtained through YouTube and was facilitated by Harbor Freight Equipment I've got on hand includes a floor jack and jack stands so stuff I'm able to do at home is a plus!

Sorry didnt mention car is a 2006 Chevrolet cobalt with the base 2.2L. No significant problems or modifications so far.

 

[darkkevin]

check engine light on? vent solenoids go bad on these a LOT. so does the wiring to the vent solenoid, causing them to be open venting gas fumes openly (check engine light would be on too, that's why i ask) otherwise the fuel pressure regulator could be bad, leaking on top of engine, usually heat dries the fuel before it reaches the floor.

 

[yote hunter]

First guess would be rust hole on the tank ? But If your fuel pump is in the top of the tank the rubber gasket could of dry rotted ??? But a 2006 should run a vacume check thru the tank and without any dash light on saying there is a problem im at a loss.... sorry, I had a bad gas cap that didn't seal tight and my engine light would come on , got a new cap and it went away on the next time the computer run its check...

 

[PaulF]

If you are smelling fuel, fuel is somewhere it doesn't belong.

Gasoline is always a fire risk. Use appropriate precautions when servicing fuel systems.

So, there are a couple of things to consider:

1) You may have over-filled the fuel tank, allowing some raw liquid fuel to run down the vent hose. Over-filling the tank (clicking it after it is full) will also allow fuel to build up in the charcoal canister. You may be smelling this fuel. The fix is to replace the charcoal canister, blow out the purge vale and lines, and stop over-fueling the car.

2) There may be a fuel leak. Look for drips. Don't smoke.

I am in Indy, if schedules permit I may be able to help.

 

[Brian Ski]

Smell seems strongest under the car on either side of the gas tank. No check engine light or problems with the functioning of the car. No smell from around the gas cap or from engine compartment.

Sorry didnt mention car is a 2006 Chevrolet cobalt with the base 2.2L. No significant problems or modifications so far.

Well from the area it sounds like the tank. This is Indiana the rust state. A lot of moisture and grit will sit on the tank and rust it. Just what I was doing yesterday. 2006 is pretty new for rust, but who knows. It does not take much of a leak to smell it. Look for dark discolorations on the tank. Maybe up toward the front and back of the tank. Also check around the straps. Get a bright light and jack it up and have a look. Sounds like a leak is just starting. Does it do it when the tank is near empty/low???

As far as the charcoal cannister... They are usually up front by the engine radiator...

 

[printcraft]

If you top off the gas tank it can flood the charcoal canister rendering it even more useless than it already is.
A small split in the gas line or return line can be hard to detect with the car not running. (plastic return lines probably)
FYI, the mother in law has a new car because she ignored the "gassy smell" from her old vehicle and it burned up.

A propane torch will detect leaks.......... I don't recommend it in the least..............

 

[PaulF]

 

[Bowman78]

.. If you have a evap system leak you should have a cel but if you drive the car on short trips it more than likely wont run evap system test.. More than likely an evap system leak ,charcoal canister damaged or flooded with fuel .. If you believe the
source of the smell is towards the rear of the car more than likely the only way to find it is an evap system smoke test...

 

[spec4]

Take it to Chevy and pay them to detect/fix it, they will be the most familiar with the model. Get it out of the garage and away from the house until fixed.

 

[Dead Duck]

Is your gas water heater with a PILOT LIGHT located in the garage?


Just be aware.













Older cars are so much easier to work on.

 

[a.bentonab]

Thanks for all the ideas. No check engine light but I only really drive 5 miles or less to and from work everyday. No gas fired appliances in the garage and I've left the garage door cracked to dissipate the smell until I get a chance later to get it up on stands and look around.

So I'm definitely guilty of the old "the pump shut off now! I can fit another dollar's worth in there!" So if there's a flooded charcoal canister what kind of fix is that?

 

[a.bentonab]

Take it to Chevy and pay them to detect/fix it, they will be the most familiar with the model. Get it out of the garage and away from the house until fixed.

I'm pretty much done with dealerships. Them ripping me off with "routine maintenance" is what sparked my interest in doing my own work in the first place. That said I am STILL waiting on my ignition recall parts and if they happen to arrive before I fix this then maybe.

 

[Brian Ski]

So I'm definitely guilty of the old "the pump shut off now! I can fit another dollar's worth in there!" So if there's a flooded charcoal canister what kind of fix is that?

Slap your hand????

Basically a longer drive will clean out the canister. May take a couple longer drive trips... Then learn to not do it. I have never really had a problem with over filling it at the gas station. Normally a charcoal canaster is either round like a coffee can or square like a brick. It is usually low up front by the radiator. Black plastic. Has tubes that fit on the top. Take a look, but from what you say it does not sound like it. I am thinking if you have been filling the tank the same way for almost a decade that may not be the problem now.

BTW what the canister does is hold the fumes from the gas tank, instead of releasing them in the air. Then when the car warms up and you are driving down the road it opens a valve to suck the fumes into the engine to burn them.

I guess you can take it to a shop for an estimate. Let them figure it out.

 

[GLOCKMAN23C]

Chances are the tank is plastic. I would lean toward the charcoal canister or the vent tube on the filler neck could be rusted through. Be sure to check the tubing that runs to and from the charcoal canister.

 

[remauto1187]

My vote... The fuel pump module O-ring is rotted out/leaking. This is what seals the module to the top of the tank. Definitely not something you want to put off or take a chance with. Keep that car out of the garage and away from the house until it is diagnosed and fixed.

Just no way it is possible that it is a fuel SUPPLY line to the engine. Fuel injected engines REQUIRE a certain amount of fuel pressure to run which is typically 45psi and up. Much less than that and the engine barely runs or wont run at all. A leak in the fuel SUPPLY line would be very obvious, fuel SPRAYING while pump is on and engine barely running or just wont start period.

 

[rjstew317]

Different direction of thought here...... have you checked the exhaust system? I had a durango with a small rust hole (or several small rust holes) in the exhaust tubing/muffler and it smelled a lot like a fuel leak

 

[PeaShooter]

helped my elderly neighbor with a gas smell from his car several years ago. It was a small rubber hose on the engine that was leaking. I don't remember exactly what it was, but it would drip gas until the pressure bled off.

 

[Leadeye]

My old car smells like gas for a day or so when it goes back in the garage, just seems normal.

 

[remauto1187]

My old car smells like gas for a day or so when it goes back in the garage, just seems normal.

That isnt normal....thats the normal lead up to an explosion and the garage burning down though.

 

[Brian Ski]

or the vent tube on the filler neck could be rusted through.

Yea I have seen that before too... Usually when driving in the rain it will toss water in the fuel tank. Sooner or later car runs really bad.