Sounds like something is either leaking or not hooked up right. Most cat back and CAI's are CARB legal and they have the toughest requirments in the country to get aftermarket approval. Tim

1941 Taylorcraft
1968 Charger
1994 Wrangler
1998 Wrangler
2008 Kia Rio
2017 Jetta

I didn't do 4 years and 9 months of Graduate School to be called Mister!