Chosen Solution

I have 99 chev350 vortex had new dual exhaust put on but didn’t weld sensors back so not hooked up will that make truck not run right or able to be tuned proper

@ogshady12 most common issues would be a sudden decrease in fuel mileage. Most commonly you will experience an overall poor vehicle performance; rough idling, stalling, hesitation on acceleration, etc. So I would suggest you redesign and find a way to connect the sensors.