Fault Code P0421
Code meaning, symptoms, possible causes, part number, and estimated cost.
P0421
Warm Up Catalyst Efficiency Below Threshold (Bank 1)
Catalyst system efficiency below threshold (Bank 1)
Part Details
Part Name
Catalytic converter
Reference P/N (OEM)
18190-28280
General part number for this fault code — not necessarily for your specific vehicle
Estimated Cost
₪2,000 - ₪6,000
Engine Location
Exhaust system
Symptoms
- Check Engine light
- Failed emissions test
Possible Causes
- 1Worn catalytic converter
- 2Faulty oxygen sensor
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