Gas Tank Makes gurgling sound

[lurtz]

Hello Everyone. I have not been on this forum in a few years, but I’m back and trying my hand at getting my 01 ssei back on the road. I have had it in storage for several years and I just recently pulled it out. I am still chasing an evap system leak code that I’ve been battling since 2018 (one of the reasons it has been in storage). Many years ago I replaced the purge solenoid, gas cap, fuel pump seal, etc but I have never been able to get rid of the check engine light that keeps it off the road.

A new symptom that I just found is when I remove the gas cap while the engine is running. Instantly the idle will run rough and surge up and down. If I stab the throttle (with cap still removed) the idle will return to normal.. ish. I can also hear a gurgling from the fuel inlet.

When I put the cap back on the idle starts to hunt around again and begins to settle down.

Any thoughts as to what might be causing my gas tank to make this noise?