Welding on car with Sniper EFI

For me, induced currents are the danger, as well as unplanned loops/ current paths: example, a sensitive sensor, and such as O2. Here you are, you have a sensor on a length of wire, terminated to a piece of exhaust. If you are welding on the exhaust, and the ground to the frame / body to the welder is better than the welder ground to the pipe, the O2 harness will see current which will try to flow back through the computer on the EFI