P1421moderate severityPowertrain
Cold Start Control
on 2003 Infiniti FX45 4.5L V8 · AWD
What this code means
The ECM detected a fault in the cold start emission control system used to warm the catalyst quickly. This affects emissions during warm-up rather than normal driving.
Symptoms
- Check engine light on
- Rough cold idle
- Increased emissions on startup
Common causes
- Faulty A/F or O2 sensor
- Ignition timing control fault
- Intake air temp sensor issue
- ECM fault
Diagnostic steps
- Retrieve freeze frame data
- Check A/F and O2 sensor operation
- Verify ignition timing control
- Inspect intake air temp sensor
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Other Powertrain codes on this vehicle
P0001
Fuel Volume Regulator Control Circuit/Open
P0002
Fuel Volume Regulator Control Circuit Range/Performance
P0003
Fuel Volume Regulator Control Circuit Low
P0004
Fuel Volume Regulator Control Circuit High
P0005
Fuel Shutoff Valve A Control Circuit/Open
P0006
Fuel Shutoff Valve A Control Circuit Low
P0007
Fuel Shutoff Valve A Control Circuit High
P0008
Engine Position System Performance - Bank 1
P0009
Engine Position System Performance - Bank 2
P0010
Intake Camshaft Position Actuator Circuit/Open Bank 1