P1491
EGR Valve Lift Insufficient
1990-2001 Acura Integra 1.8L I4 🇨🇦
Moderate SeverityPowertrain
Description
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.
Other Powertrain Codes
- P0001Fuel Volume Regulator Control Circuit/Open
- P0002Fuel Volume Regulator Control Circuit Range/Performance
- P0003Fuel Volume Regulator Control Circuit Low
- P0004Fuel Volume Regulator Control Circuit High
- P0010Intake Camshaft Position Actuator Circuit/Open Bank 1
- P0011Intake Camshaft Position Timing Over-Advanced Bank 1
- P0012Intake Camshaft Position Timing Over-Retarded Bank 1
- P0013Exhaust Camshaft Position Actuator Circuit/Open Bank 1
- P0014Exhaust Camshaft Position Timing Over-Advanced Bank 1
- P0015Exhaust Camshaft Position Timing Over-Retarded Bank 1
P1491 on Other Vehicles
Common Questions
What does code P1491 mean on a 1990-2001 Acura Integra?
P1491 stands for "EGR Valve Lift Insufficient". The EGR valve is not lifting enough to allow commanded exhaust gas recirculation.
What are the symptoms of P1491 on a Acura Integra?
Common symptoms of P1491 include: CEL, Increased NOx, Failed emissions, Engine knock possible, Rough idle.
What causes P1491 on a 1990-2001 Acura Integra?
Common causes of P1491 include: Carbon buildup, Faulty EGR valve, Clogged passages, Vacuum supply issue.