P1491moderate severityPowertrain
EGR Valve Lift Insufficient
on 1997 Acura RL 3.5L V6 · AWD
What this code means
The EGR valve is not lifting enough to allow commanded exhaust gas recirculation.
Symptoms
- CEL
- Increased NOx
- Failed emissions
- Engine knock possible
- Rough idle
Common causes
- Carbon buildup
- Faulty EGR valve
- Clogged passages
- Vacuum supply issue
Diagnostic steps
- Clean EGR passages
- Test EGR valve
- Check vacuum supply
- Inspect position sensor
Repair notes
Clean EGR system or replace valve.
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Other Powertrain codes on this vehicle
P0001
Fuel Volume Regulator Control Circuit/Open
P0001
Fuel Volume Regulator Control Circuit/Open
P0002
Fuel Volume Regulator Control Circuit Range/Performance
P0002
Fuel Volume Regulator Control Circuit Range/Performance
P0003
Fuel Volume Regulator Control Circuit Low
P0003
Fuel Volume Regulator Control Circuit Low
P0004
Fuel Volume Regulator Control Circuit High
P0004
Fuel Volume Regulator Control Circuit High
P0010
Intake Camshaft Position Actuator Circuit/Open Bank 1
P0010
Intake Camshaft Position Actuator Circuit/Open Bank 1