Oh Dear Bob,
Yes this will cause problems.
#1 it's illegal. Federal regulations say every vehicle that came from the factory with a cat needs to have a cat. They are used to reduce harmful emissions from the atmosphere. They are used to reduce harmful emissions from the atmosphere.
〉 Answered on Sep 16th, 2014 by Amy Mattinat, Owner and Author at Auto Craftsmen Ltd
Removing a catalytic converter is illegal, both federally and in most states. If you have emissions testing, you will not pass. I would not recommend this.
〉 Answered on Sep 16th, 2014 by Gail Dunn, Owner at Women's Automotive Connection
It won't pass smog
〉 Answered on Sep 16th, 2014 by Gelina Aquilina, Service Advisor / Mechanic at
Bob, On your 2004 Pontiac: I recommend replacing a bad catalytic converter NOT removing. Removing is illegal. Catalytic converter reduces harmful vehicle emissions. A check engine light will appear without a catalytic converter and a vehicle will not pass smog or emission testing.Good Luck.
〉 Answered on Sep 16th, 2014 by Maryann Croce, Owner at Croce’s Transmission Specialists