I have not heard of any ABS plumbing issues. Do you know what might be causing it? A nylon string can be used in close quarters to cut the pipe by sawing it and the heat from friction will cut it in half. Good luck and keep us posted.
Mike, RVIA & RVSA Certified Master RV Technician
Amy, Dr. Assistant - Roxie & Mei Ling, four legs each
2000 Gulf Stream Scenic Cruiser 450 hp & 1330# torque
06 Saturn Vue, 06 Chevy Z71 4x4 & 2014 Corvette Z51 M7