- Oxygen Sensor Failure
- Faulty or Loose Gas Cap
- Catalytic Converter Issues
- Ignition Coil Problems
- Evaporative System Leaks
- MAF (Mass Air Flow) Sensor Failure
- Bad/Old Spark Plugs.
If your 1995 Lexus LS 400 displays a persistent check engine light, getting immediate diagnosis is recommended through professional diagnostics with a scan tool to determine the underlying issue and receive appropriate repairs .