The one thing the original poster failed to tell us, is where this car is driven or where he/she is located! If it's down in the desert southwest then keeping the heat shield on is a must. If it's up here where we have real winters half the year, then not as big of a deal My son't 2009 Vibe GT rear...

I don't think removing the heat shield between the exhaust system and the fuel tank is a very smart move.

I searched for help on the ToyotaNation forum, since the Toyota Matrix and the Pontiac Vibe are near-identical twins, and found a report that that plastic part became unavailable years ago. (So I suggest that the part that Dorman &co. list as only for models up to 2007 should in fact be consider...

Our 2008 Vibe's heat shield (the one between the exhaust and the fuel tank) has detached at the rear where a bolt originally screwed into a plastic piece that is attached to the fuel tank strap. I could not see this clearly until I raised the back of the car as much as I could and was able to crawl ...