What visual evidence would indicate catalytic converter tampering?

• A. Properly installed catalytic converter with a shield
• B. A catalytic converter that is brand new
• C. A catalytic converter with a leak
• D. Missing catalytic converter or replacement with a non-emission device

Answer: (D)

Tampering shows up when the catalytic converter isn’t there or has been swapped for something that doesn’t perform emissions control. The clearest visual evidence is a missing catalytic converter or a straight pipe (or another non-emission device) in its place. That directly bypasses the catalytic converter and reduces emissions, which is the essence of tampering.

Why the other signs aren’t definitive on their own: a properly installed catalytic converter with a shield looks normal and doesn’t indicate tampering; a brand-new converter could simply be maintenance or replacement; a leak points to wear or damage rather than intentional bypass.