P0491low severityPowertrain
Secondary Air Injection System Insufficient Flow Bank 1
on 2019 Toyota RAV4 2.5L I4 (A25A-FKS, Dynamic Force) · FWD
What this code means
The PCM has detected insufficient secondary air flow on bank 1. This reduces the system's ability to lower emissions during cold starts.
Symptoms
- Check engine light on
- Failed emissions test
- Rough cold-start running
Common causes
- Faulty secondary air pump
- Clogged air passages
- Stuck air injection valve
- Damaged wiring or hoses
Diagnostic steps
- Scan for stored codes
- Test secondary air pump operation
- Inspect air injection valves and hoses
- Check for clogged passages
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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