Question: What are the penalties in Minnesota for removing a catalytic converter on a vehicle if the sound level of the car is kept reasonable? Is there a specific law that prohibits the removal of the cat or are they more pertaining to the sound level that is produced form the process? Also, if you know what the statute is that identifies requirements for the exhaust system of a vehicle, that would also be appreciated.

Answer: Your question makes some false assumptions and mixes things up a little. The sound level of the vehicle is a different issue than the catalytic converter. To put it very simply, the exhaust system laws require that the sound of the exhaust has to blend with the overall noise of the vehicle. The statute number dealing with exhaust systems is M.S.S. 169.69. Fines for loud exhaust currently average around $127.

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Removal of catalytic converters is a whole different story. The removal without replacement of a catalytic converter by individuals or automotive servicers is a violation of Section 203(a)(3)(B) of the federal Clean Air Act.

The intent of this law is to protect our air quality and not to reduce noise levels. A catalytic converter is one of the most important pollution control devices on a car. It burns fuel that was not completely used by the engine, which prevents emission of air pollutants.

This law requires

vehicles to retain their original manufacture-certified configuration for emission control equipment. The only exceptions are for racing or vintage display vehicles.

The federal Environmental Protection Agency (EPA) enforces this law, which has a maximum civil penalty for violation by a dealer or manufacturer of $25,000 and for any other person $2,500.

For additional information about catalytic converter laws, contact EPA Vehicle Emissions Controls.

If you have any questions concerning traffic-related laws in Minnesota, send your questions to Trooper Jesse Grabow, Minnesota State Patrol, 1000 Highway 10 West, Detroit Lakes MN 56501-2205. Or reach me at