Is a catalytic converter part of an engine warranty?

Usually not. On most vehicles, the catalytic converter is covered under an emissions (emission-control) warranty, not the engine or powertrain warranty. In the United States, federal law generally requires at least 8 years/80,000 miles of coverage for the catalytic converter, while “engine” or “powertrain” warranties typically exclude emissions components unless there’s overlap due to a related engine defect or a brand-specific policy.

How warranties classify a catalytic converter

Automakers separate coverage into categories, which is why a catalytic converter is treated differently from the engine block, pistons, or crankshaft. Understanding these categories clarifies why your converter is typically not in the “engine” bucket.

• Engine/powertrain warranty: Covers mechanical components that produce and transmit power (e.g., engine internals, transmission, drivetrain).
• Bumper-to-bumper (limited) warranty: Broad coverage with many exclusions and a shorter term than powertrain.
• Emissions (emission-control) warranty: Specifically covers parts that manage tailpipe emissions—this is where the catalytic converter almost always lives.
• Corrosion and ancillary warranties: Separate coverage for rust-through and other body-related issues.

Because the catalytic converter’s sole purpose is emissions control, it is grouped with emissions systems by law and by automaker policy rather than with core engine components.

How coverage typically works in the United States

Federal emissions warranty (EPA/Clean Air Act)

For light-duty vehicles sold in the U.S., federal law requires two levels of emissions coverage: a 2-year/24,000-mile warranty for all emissions-related parts, and an 8-year/80,000-mile warranty for “major emissions control components.” The catalytic converter is one of those major components, along with the powertrain/emissions control computer (ECU/PCM) and the onboard diagnostics device.

CARB states and longer terms on some vehicles

In California and states that follow California Air Resources Board (CARB) rules, some vehicles carry longer emissions coverage. As a baseline, the catalytic converter still has at least the federal 8-year/80,000-mile protection. Certain models—especially those certified to partial zero-emission vehicle (PZEV) standards—have extended emissions warranties that can reach up to 15 years/150,000 miles for specified emissions components. Many brands also provide 7-year/70,000-mile coverage for qualifying high-cost emissions parts in CARB states. Always check your vehicle’s warranty booklet for the exact terms.

Overlap with powertrain warranty and “consequential damage”

If an engine defect (e.g., excessive oil consumption or misfire caused by a covered engine part) damages the catalytic converter, the manufacturer may cover the engine repair under the powertrain warranty and the converter under emissions warranty—or, in some cases, apply “consequential damage” coverage or goodwill. The specifics vary by brand and diagnosis.

Outside the U.S.: what to expect

Coverage for catalytic converters is jurisdiction-specific. In Canada, many manufacturers mirror U.S.-style emissions warranties, often around 8 years/130,000 km for the converter and engine control module, but you should confirm in your warranty guide. In the EU and UK, statutory consumer guarantees and emissions durability requirements exist, yet there is no single emissions warranty standard equivalent to the U.S. 8/80; actual coverage depends on the manufacturer’s policy and local law.

When the catalytic converter may not be covered

Even within an emissions warranty period, certain conditions can lead to a denial. These common exclusions explain when coverage typically doesn’t apply.

• Tampering or modifications (e.g., cat delete, non-compliant tuning, removal of O2 sensors).
• Aftermarket converter that is not EPA- or CARB-certified for your vehicle.
• Damage from misfueling (e.g., leaded fuel), coolant or oil contamination due to non-warranty causes, or neglect.
• Use outside design intent (e.g., dedicated off-road/racing use) or failure to address check-engine warnings.
• Mileage/time beyond the emissions warranty period or lack of proof of proper maintenance where required.
• Theft: replacement is typically an insurance (comprehensive) claim, not a warranty item.

If any of these conditions apply, a dealer or manufacturer may deny the claim, or limit it to related covered components only.

How to verify your coverage and what to do next

Before authorizing repairs, follow these steps to confirm whether your catalytic converter is still covered and to strengthen a claim if it is.

1. Locate your warranty booklet: Look for sections labeled “Emissions Control Warranty.”
2. Confirm in-service date and mileage: Emissions coverage is based on time from first retail sale and total miles.
3. Check the under-hood emissions label: Note U.S. EPA vs. CARB certification and whether the car is PZEV or SULEV.
4. Retrieve diagnostic trouble codes (e.g., P0420/P0430): A dealer report helps anchor the warranty claim.
5. Ask the dealer to reference federal/CARB warranty provisions: Specifically the 8-year/80,000-mile major emissions component coverage.
6. Review technical service bulletins or extended coverage programs: Some models have special policies for catalyst issues.
7. If denied, request a written reason and escalate: Contact the manufacturer’s customer care, BBB Auto Line (where applicable), or relevant regulators (EPA/CARB) if you believe the denial conflicts with law.
8. Out of warranty? Consider goodwill assistance or insurance (for theft) and ensure any replacement cat is certified (EPA/CARB) for your vehicle.

Documenting the vehicle’s status and citing the correct emissions statute or state program often speeds up fair resolution and reduces out-of-pocket costs.

Costs, parts, and replacement notes

Out-of-warranty catalytic converter replacement with OEM parts can range from roughly $800 to over $2,500 per converter (more for some luxury or multi-cat systems). It is illegal in many jurisdictions to remove or disable a catalytic converter. In the U.S., any replacement must meet EPA requirements, and in CARB states you must use a CARB-certified unit matched to your vehicle. Diesel vehicles use aftertreatment systems (DOC, DPF, SCR); their catalysts are also covered under emissions warranties, though timelines and components may differ by class and certification.

Key takeaways

These points summarize how catalytic converter coverage typically works and what that means for your repair or claim.

• In most cases, the catalytic converter is not part of the engine or powertrain warranty; it’s covered by the emissions warranty.
• U.S. federal law provides at least 8 years/80,000 miles of coverage for the catalytic converter; CARB states may offer longer coverage on some vehicles.
• Failures caused by covered engine defects may bring overlap or goodwill, but exclusions (tampering, non-compliant parts, neglect) commonly void coverage.

Knowing which warranty applies—and when—helps you avoid unnecessary expenses and ensures repairs are handled under the proper legal and manufacturer frameworks.

Summary

The catalytic converter is generally not part of an engine warranty. It is typically covered under a separate emissions warranty—at minimum 8 years/80,000 miles in the U.S., with potential extensions in CARB states or by specific manufacturers. Coverage can overlap if an engine defect leads to catalyst damage, but tampering, non-compliant replacements, or neglect often void claims. Always verify your vehicle’s exact terms in the warranty booklet and confirm eligibility with a dealer using your VIN and diagnostic results.

How much does it cost to get a catalytic converter replaced?

The average cost of having a new catalytic converter installed is between $2,224 and $2,309, according to the car repair estimate site RepairPal. However, this won’t necessarily be the absolute cost range for every person who needs to get one.

Will insurance cover catalytic converter replacement?

If you have comprehensive coverage on your auto insurance policy, then you’re typically covered against catalytic converter theft. Comprehensive coverage will typically pay to replace the stolen catalytic converter and repair any related damage from its removal.

Is the catalytic converter considered part of the engine?

No, the catalytic converter is not part of the engine; it is a component of the exhaust system, located between the engine and the muffler. Its purpose is to chemically convert harmful exhaust gases produced by the engine into less harmful substances, such as carbon dioxide and water, before they are released from the tailpipe.
 
What the Catalytic Converter Does

• Reduces Harmful Emissions: The catalytic converter uses chemical catalysts to transform toxic pollutants from the engine, like carbon monoxide and hydrocarbons, into safer gases. 
• Filters Exhaust Gases: It acts as a filter for the exhaust, treating the gases to reduce their environmental impact and meet legal requirements. 

Location 

• Between the Engine and Muffler: You can find the catalytic converter underneath your vehicle, situated in the exhaust pipe after the engine but before the muffler.

Does the engine warranty cover a catalytic converter?

The catalytic converter is often covered under a vehicle’s factory warranty. That’s usually not the case for extended warranties.