I recently bought a 2003 Mustang GT with a Roush CAI on it. I've been noticing problems when I first start the car and put it in gear (it's an automatic). As soon as I put it in gear the rpms jump up and down like the car is going to die if I don't give it gas soon. A friend of mine said that my car is likely not tuned and that the Roush CAI is bogging it down and causing it to almost die. Does anyone know if that makes sense? I'm looking for someones opinion and for that matter is it worth it to tune it anyway?
A lot of cold air intakes do require a tune for it to work properly. Not sure about the roush for your year, though. You can check on americanmuscles website for that intake and your year and it should say whether a tune is required or not.