P0420 on Ford Vehicles
The bank 1 catalytic converter no longer stores enough oxygen to clean the exhaust properly. P0420 →
27Complaints mentioning the code
#5Rank among 14 brands
1.0%Share of Ford DTC complaints
In NHTSA owner complaints we analyzed for Ford, P0420 was mentioned 27 times.
Most mentioned models
| Ford Focus Bev | 8 | |
|---|---|---|
| Ford Focus | 6 | |
| Ford F-150 REGULAR CAB | 2 | |
| Ford Taurus | 2 | |
| Ford Ecosport | 1 | |
| Ford Edge | 1 |
Model years mentioned
Components named in these complaints
- Fuel/propulsion System (13)
- Engine (9)
- Power Train (6)
- Unknown Or Other (4)
- Electrical System (3)
Reports with a crash: 1 · fire: 1 · injuries: 0
Often appears together with
P0456
Powertrain
The EVAP system has a tiny leak, about 0.020 inch — the hardest EVAP leak to find, and often…
Minor
P0430
Powertrain
The bank 2 converter on a V6, V8 or split-exhaust engine isn't cleaning the exhaust well enough.
Low
P0443
Powertrain
The ECU detected an electrical fault in the purge solenoid circuit: open, shorted or a bad…
Low
P0452
Powertrain
The tank pressure sensor signal is stuck near 0 volts, lower than the sensor can physically…
Minor
P0460
Powertrain
The engine computer gets no usable fuel level signal – often a tank-top connector or the sender…
Low
Possible causes
- Catalytic converter worn out or poisoned by age, oil ash, coolant or silicone
- Rear (downstream) O2 sensor slow, contaminated or reading out of range
- Exhaust leak ahead of the rear O2 sensor (manifold, gasket, flex pipe)
- Engine fault that overheated the converter: misfire, rich mixture, leaking injector
Related codes
Source: NHTSA Complaints API (US government open data), analyzed by DTC mention.