Federal emissions warranty can cover certain major components for 8 years or 80,000 miles, whichever occurs first; it is not a blanket warranty for every emissions part.
This reference supports the stated topic only. Model, model year, equipment, current rule or individual vehicle conditions may differ; check the original source before acting.
Read the EPA original: Emissions Warranties for 1995 and Newer Cars and Trucks Source date: 2012; research checked: 2026-11-01.
What the federal rule addresses
EPA identifies specified major emissions components including the catalytic converter and emissions control computers. Check the warranty booklet, original in-service date, state rules and exact component before assuming coverage.
What to ask
Give the dealer the VIN and the diagnosed component. Ask for the applicable federal and state emissions warranty terms in writing before ordering a replacement.
Which components the federal period names
EPA's emissions-warranty guidance identifies three specified major components: catalytic converters, the electronic emissions control unit or computer, and the onboard emissions diagnostic device or computer. The eight-year or 80,000-mile period ends when either limit is reached. It does not automatically extend to every oxygen sensor, valve, hose or exhaust part.
Coverage also depends on the vehicle category, first in-service date, the diagnosed defect and the manufacturer's warranty procedure. California and some other programs may provide different or additional coverage. Before paying for a converter, gather the VIN, warranty booklet, repair diagnosis and emissions-test report if relevant, then ask the manufacturer for a written coverage determination.
What a code does not prove
P0420 or P0430 does not establish that a catalytic converter has failed, so neither a code reader nor this page can promise warranty payment. The shop must identify the actual component and cause. If a misfire, exhaust leak or mixture problem remains, a new converter may not solve the warning.
Sources and scope
- EPA — Emissions Warranties for 1995 and Newer Cars and Trucks Document: 2012 · Research checked: 2026-11-01
Research snapshot: 2026-11-01. Source documents may have newer revisions. Verify current instructions and VIN eligibility with the manufacturer.