Got two codes for Power Steering Pressure Sensor P0550
And EvaP system small leak P0442

Happened right after muffler delete, is it due to the muffler delete or just coincidence?

 

Put the muffler back on, reset the ECU and see if the problem goes away. That should answer your question.

 

It was done at a shop and was welded, so that's not happening. lol

 

Then take it back to the shop and tell them they did something that caused the car to throw a couple codes. Or, at least check to make sure they didn't unplug any sensors and forget to plug them back in after they finished the job.

 

The a muffler swap only would have no effect on those codes. Just delete them and see if they come back