Popping noise coming from fuel tank??

[01ROSALESLS]

Occasionally I hear this "pop" come from my car. It comes from the rear of the car, sounds like the fuel tank is burping or something. I usually hear it at idle, like when the car is warming up or at a stop sign/light. Any ideas? I've had my LS for almost 2 years and have heard this since day 1. It's just getting annoying! I can't figure out what it is. It happens whether the car has a full tank, empty or anywhere in between.
Joe

 

[gcwimmer]

Sounds like heat expansion and contraction of the exhaust system. Your fuel tank is under the rear seat area.

 

[pektel]

Yep, mine used to do that all the time too... I always thought it was the muffler. I just put on magnaflow mufflers and new pipe from the resonators back, and no more popping noise.

 

[01ROSALESLS]

Thanks! You just gave me perfect reasoning to get a new exhaust system.
Joe