This may be a stupid question, but be awesome and help me out . I just bought a Haltech PNP and before I take it to my tuner, I have a question. I plan to have a local shop install a 3" stainless exhaust with test pipe, and Im sure the CEL will come on with the O2 sensor in the test pipe. Will it make the car act up or hurt anything before I make it to the tuner? Thanks!

 

You can add the exhaust and test pipe's first. Want hurt a thing