02' TJ, 4.0L, 5spd, 41,000mi.
After daily 15mi commute with engine off getting loud knocking noise from what seem inside the fuel tank. Can feel the viprations through rear tires. Started happening about a week ago and usually lasts about 5-10min then goes away. No CLue except have had an ASD code for about a year which my mechanic and dealer can not track down.