From time to time I smell fuel while in the car driving. I don't physically see a leak anywhere so what is a good way to determine where this is coming from? Could it just be the fuel cap not sealing properly? I barely turn the fuel cap to the left and it comes off, but when I put it on it will click like it is sealing. Any thoughts on where the smell could be coming from?

 

Open up the fuel pump cover door and see if there is any fuel accumulated on top of the pump itself. May be leaking at that point.

 

I had a fuel leak once at the fuel filter. The filter is supposed to mount to the expansion tank via a plastic clip/retainer. Mine broke and the filter was rubbing on the top of the engine allowing a pinhole of fuel to escape.

 

Where is the fuel pump cover? I will give that a try.

 

worn injector o ring could be a culprit too, does your garage smells like fuel too?

 

Front trunk. Four 10mm cap nuts to remove plastic cover.

 

Yep very easy to get to and either rule in or out this possibility.

 

I just had the fuel filter replaced by the dealer just as a maint. item since the car is an 01 with low miles.

 

The garage doesn't smell like fuel at all. Only in the cabin when driving from time to time.

 

Fuel pump cover is clean and dry. No smell of fuel there either.

 

The filter is supposed to mount to the expansion tank via a plastic clip/retainer.

 

See gas cap. Maybe ?

 

Did it only start after the dealer worked on it? Stating the obvious perhaps, but check anything that was recently changed first to see if it wasn't fully installed or secured properly.

 

What you might check:

Try to take the cover in the trunk of again, pull of the line that is only for
the air to get out of the tank and blow inside that side that is in the tank cover.
(Maybe use a second hose so you dont have to put your mouth on it)

On my car there was a leakage in one of the connector pins on top of the white cover (Fuel pump connector) that the air came out. You will hear it.
It is a known problem that the fuel pump connection may corrode. The resistance raises and as the contacts get warm. they melt the plastic and smell is released.