i just replaced the vapor lines on the top of my tank for that very reason, fumes were terrible every time i filled until it got below 3/4 tank. No cel ever came on either. The fuel when leaking out would run off the top of the tank and collect inside the metal shield so no fuel ever dripped on the ground. Replacing the vapor lines completely fixed the problem, since I had the tank out I went ahead and replaced the fuel pump. Just in case. They are still available on line.

These are the lines on mine that were leaking
https://www.carparts.com/details/Chevrolet/HHR/AC_Delco/Fuel_Tank_Vent_Hose/2008/AC22719581.html?TID=gglpla&origin=&utm_source=goog le&utm_medium=pla&utm_campaign=12886175984&gclid=C j0KCQiAtJeNBhCVARIsANJUJ2ErgERH0KpbbyP8eo3SZsYHV6n oYSqUgR930xOS-ogc6D3wAMlCExcaApO7EALw_wcB&gclsrc=aw.ds

 

RTV won't hold up to gasoline very well, don't know how long it will last though with just intermittent exposure.
We have always used Devcon Narine-Tex for marine tanks, it's an epoxy just for tank leaks.
Best of luck.

 

Were you plastic fittings on the tank cracked as well?

 

I got same gas smell after filling up….and see nothing wet or dripping on ground. Not really any smell in the car though. Thanks for info. Well look asap

 

The vapor line won't drip but does smell.

 

In September, started smelling a strong gasoline odor inside the car when the tank was full. Ordered the vapor line assembly from Rock Auto and installed it today. This is what the top of the tank looked like before I cleaned it and installed the new vapor lines.

 

I had a similar problem on my SS for most of 2 years. Never saw anything on the ground, until it started smelling stronger. Just by luck as I was getting out of it in my garage, it seem very strong. Used a flashlight to look around, and saw one tiny droplet hit the floor and disappear. A small gas leak, a small quick to evaporate droplet, and parking in the same spot OVER the evidence on the floor. Got it up on a lift and felt the fuel line heat resistant fabric on the lines going up the left side behind the LR wheel, sure enough fuel leaking from the lines. The material is to keep heat off the fuel lines, but the way it's installed, it traps water inside it. My SS is a 2008, and at 100K miles, the lines were destroyed from outside in. Was just getting an Arthritis attack that year, couldn't reach over my shoulders. I had the money, wanted only factory parts, so took it to a local dealer. Yeah cost a bunch, $700. Didn't care, had a free brand new Chevy pickup as a loaner. And those 2 lines? They are about 7 feet long each. Anyway that was an easy fix for me. LOL My idea would be to use side cut pliers and cut a small notch of material out at the lowest points, so the water can't collect inside the material, and then soak it down with "Blaster" penetrating spray from a small cut out at the higher points. That would slow down the rusting.

 

Up here, we even have products like Rust Check and Krown rust proofing spray.

 

2011 2.2 LT HHR….I got same issue, smell gas after I fill it. Read posts.
Is there any way to see the vapor lines with an inspection mirror on top of the tank? Also…what all is involved in dropping the tank?

Thanks

 

Empty fuel tank, by running it down till the low fuel light comes on.
you can’t see up over the tank, no room.