Nissan code
P0420: on a Nissan
How much to fix P0420 on a Nissan? Typically $430 to $2,325 for catalytic converter replacement, the most common fix. This is an estimate, not a quote.
Nissan owners often hear "you need a new converter" right away. Sometimes that is true, and sometimes the front sensor is the only part that failed. Nissan 2.5 engines are known for oil use, which can ruin a converter over time.
General meaning of P0420: The computer compares the oxygen sensor before the catalytic converter with the one after it. On this code the two readings look too alike, which suggests the converter is not cleaning the exhaust as well as it should on the side with cylinder 1. See the full P0420 page.
Models to know about
| Model | Years | What to know |
|---|---|---|
| Altima | 2007 to 2016 | The 2.5 engine has many repair cases with converter trouble and oil burning. |
| Sentra | 2007 to 2019 | Smaller engine, the sensor and the converter share the blame. |
| Rogue | 2008 to 2020 | 2.5 engines mostly; check oil use. |
| Maxima | 2004 to 2015 | V6 with two converters. |
Common causes on a Nissan
- Oil burning on the 2.5 that coats the catalyst.
- Front air-fuel sensor wearing out and misreporting.
- Misfires from worn plugs or coils that overheat the converter.
- Exhaust manifold leak on cars from the rust belt.
NHTSA's public complaint file shows how owners describe this kind of trouble: the 2009 Nissan Altima has 1,547 complaints on file, and 44 of them use wording like catalytic, check engine, P0420, oil; the 2012 Nissan Rogue has 319 complaints on file, and 24 of them use wording like catalytic, check engine, P0420, oil. Complaints are owner reports, not proof of a cause.
Check this first
- Check the oil level between changes for two weeks. A pint low in 1,000 miles is a clue.
- Pull codes for misfires (P0300 range). If present, fix those first.
- Look for sooty marks at the exhaust manifold gasket.
Wide range: this job varies a lot. Itemize your quote for a better answer.
How this range is built
| Part of the job | Low | High |
|---|---|---|
| Parts | $300 | $1,900 |
| Labor: 1.2 to 2.5 hours × $110 to $150 an hour | $132 | $375 |
| Fees: shop supplies, disposal, diagnostics | $0 | $40 |
| Total, rounded | $430 | $2,325 |
The hourly rate is the BLS Occupational Employment and Wage Statistics, May 2025 average pay for this trade in the US, $27.13 an hour, times 4 to 5.5 to cover what a shop bills (overhead, tools, insurance, profit). Parts are a band from budget aftermarket to the manufacturer part. In California and New York, parts cost more because those states require a California-certified converter. Full method.
Not a repair shop, estimates only. Typical range, estimate. Not a quote. Your car, parts and shop change the number.
Nissan converters are bolted to the manifold on many models, which makes them harder to swap and raises labor. Pre-converter sensors are inexpensive.
Other repairs that may be involved
| Repair | Typical range, US |
|---|---|
| Catalytic converter replacement | $430 to $2,325 |
| Oxygen sensor replacement (one sensor) | $100 to $350 |
Questions to ask the shop
- Is the oil level and consumption checked?
- Is the front sensor tested?
- Does my state require a CARB converter?
Got a quote already? Check it against the range. Wondering if a recall touches this problem? See Nissan recalls by model or check a VIN.
P0420 on a Nissan: questions
Will new plugs fix P0420?
Only if worn plugs caused the misfire that damaged the converter, and then probably not.
Is there a Nissan recall for it?
Check your VIN. This code is not a recall item by itself.
How much does it cost to fix P0420 on a Nissan?
The most common fix, catalytic converter replacement, has a typical range of $430 to $2,325 across the US. That is an estimate built from parts prices and local labor wages, not a quote. Your model, engine and shop move it.
P0420 on other makes
Sources
- NHTSA complaints, 2009 Nissan Altima
- NHTSA complaints, 2012 Nissan Rogue
- NHTSA recall lookup by VIN
- US federal emissions defect warranty rules (40 CFR part 85, subpart V)
Written from public NHTSA data, owner-reported patterns and general repair knowledge, in our own words. Model lists are examples, not a full list, and patterns are not a diagnosis. Prices updated October 2026. Not a repair shop, estimates only.