Sup guys. This sound is a first for me. I've got a 2002 Max.

At idle, no matter if its a cold start or the car has been running an hour, I hear a strange gurgling with a quiet high pitched whine coming from my stock muffler. Almost as if a liquid is boiling. The noise is fairly silent, I can only hear it at idle, but at idle it is definitely audible. The odor of the muffler indicates everything is working fine.

Car performance isn't altered in any way. WTF is it? The only mods to the engine is an Injen Air Intake. Its puzzling me...

 

Remove the muffler and see if it is full on water......

 

I was finally able to examine my car this weekend and noticed the sound is actually a vibration coming from the gas tank. The sound was coming from the muffler because they were rubbing against each other.

I think the fuel pump is acting up. The car only has about 90k miles on it though. Hmm.

Any suggestions? I'm shopping around right now for fuel pump prices. Let me know if there are any companies I should know about online. Thanks.

 

I know this is an old thread but im hearing the same gurgling noise near the gas tank area, as if something is boiling also. What happend to fix the problem?

 

air in the return line