GenVibe - Community for Pontiac Vibe Enthusiasts

After driving the Vibe for a few minutes, I heard a huge noise like metal on concrete in the rear. It happened once every time I drove it.I took it to the dealer, they heard the noise. The gave me a rental becuase they couldn't find the cause. They had a guy lay in the back to idenify source. They pulled the car apart, and found nothing. They figured it must be the gas tank. They replaced the gas cap and the sound went away. They described the issue of improper seal when gas tank reached optimal pressurization.After I got the new gas cap I was good for weeks, but I just heard the sound again.Anyone else ever have a similar issue?

...haven't experienced anything like that with our 2009 Vibe....could it possibly be a loose or vibrating license plate?

I have experienced that personally . . . but nothing to do with the Vibe.

Check to see if the spare tire compartment and the little one behind the rear seat are locked. I've left the spare tire compartment unlocked before and it does sound weird when you hit a bump and the cover bounces open!Also check to see if the exhaust is attached properly to it's hangers!

Possible bad strut mount or strut?

They are on the right track, but now they may look at the fuel pump or the pump pressurizing the tank / purge system etc. Friend of mine just went through this same issue with her new VW Golf, the internal pump was over pressurizing the system...

You give your mother in law a ride somewhere every day?

Thanks for response. Your description of the pump pressurizing the tank / purge system over-pressurizing the system sound exactly like what is happening.To everyone else - thanks for the laughs!