Frequently Asked Questions

What is the most common reason for check engine light on a 2023 Lexus IS 500?

• Loose or damaged gas cap is the simplest and most frequent cause—an easy fix that clears the code quickly.
• Faulty oxygen sensors or catalytic converter issues are common on higher-mileage vehicles and affect emissions and fuel economy.
• Fuel trim or air/fuel mixture problems (vacuum leaks, dirty MAF) can trigger codes and reduce performance in the 5.0L V‑8.
• Ignition misfires (spark plugs, coils) are especially important to address on an eight‑cylinder engine to prevent further damage.

What does it mean when the check engine light comes on in a 2023 Lexus IS 500?

• It indicates the vehicle’s onboard diagnostics (OBD‑II) detected a system issue—anything from emissions faults to engine misfires.
• Light steady = a stored fault that should be diagnosed soon; flashing = active severe fault that needs immediate attention.
• Codes help pinpoint the system (fuel, ignition, emissions, EVAP, sensors), but a full diagnostic is needed for an accurate repair plan.
• For warranty-covered items, repairs must be performed at a certified dealership to retain coverage and ensure OEM parts.

What is the first thing to check when the check engine light comes on?

• Check the gas cap: ensure it’s tight and undamaged—this often resolves an EVAP leak code.
• Look for obvious issues: low fluid levels, loose hoses, visible engine damage, or disconnected sensors.
• Note any performance changes: stalling, rough idle, loss of power or unusual noises to tell the technician.
• Bring the vehicle to a certified service center promptly; dealer diagnostics ensure accurate code reading and OEM repairs when required by warranty.

How much does a check engine light diagnostic cost for a 2023 Lexus IS 500?

• Diagnostic rates vary; a typical dealer scan and initial inspection often ranges from a modest flat fee to a short labor charge depending on complexity.
• At Nalley Lexus Roswell, factory-trained technicians use OEM tools for faster, more accurate diagnostics—often saving you money versus repeated independent attempts.
• Dealership service emphasizes immediate and long-term savings: correct first-time repairs, OEM parts, and warranty protection reduce future expenses.
• If a repair is covered under warranty, the work must be completed at a certified dealership to ensure coverage and quality.

How long does a check engine light service take?

• Initial OBD‑II code reading and basic inspection typically take 30–60 minutes.
• Follow-up diagnostics (road test, component testing) can extend the visit to 1–3 hours depending on complexity.
• Actual repair times depend on the issue—simple fixes like a gas cap or spark plug change are quick; catalytic converter or internal engine repairs take longer.
• Scheduling service at Nalley Lexus Roswell ensures efficient turnaround with factory-trained technicians and genuine parts, often minimizing repeat visits and long-term costs.