Was wondering if installing some long tube headers and new mufflers .....would that trigger a check engine light?

 

Well, you would have to get a Shorty mid pipe, if you get an o/r h or x then yes, you will either have to get a tune or mils to get rid of it, depending on the year your car is. If you get a catted x or h then its a hit and miss, the cats may be so free flowing that it may trigger a cel. BUTTT, if your getting longtube headers you will need a tune anyways, so you can just turn off the rear O2 sensors with it. In short yes they will, but you need a tune anyways so problem solved.