The Toyota Corolla 1.6 is known for reliability, but one frequent complaint is the check engine light illuminating and staying on. This lamp means the ECU has detected a fault in a sensor/system — sometimes minor, sometimes serious.
Symptoms
- Constant or flashing check engine light
- Reduced engine performance
- Increased fuel consumption
- Rough or unstable idle
Main causes
- Faulty oxygen (O₂) sensor
- Clogged catalytic converter
- Faulty spark plugs or ignition coils
- Loose/faulty fuel cap
- Dirty/sticking EGR valve
Solutions
- Read fault codes with OBD-II scanner
- Replace faulty sensors/catalytic converter
- Replace spark plugs/coils
- Check/replace fuel cap
- Clean or replace EGR valve
Advice
Don’t ignore the CEL. A flashing light indicates active misfire and can damage the catalytic converter. Get an OBD check early to avoid higher repair costs.
