Frequently Asked Questions

How long does a check engine light service take?

• Initial diagnostic scan: typically 30–60 minutes using dealer-grade OBD-II tools to read codes and freeze-frame data.
• Inspection and road test (if needed): add 30–60 minutes depending on symptoms and whether intermittent codes appear.
• Simple fixes (sensors, gas cap, software updates): often completed the same day.
• Complex repairs (catalytic converter, engine repairs): may require parts ordering and take days; we provide timelines and loaner options when available.
• Choosing Nalley Lexus Roswell often costs less than independent shops overall because precise diagnostics prevent repeat repairs and protect warranty coverage.

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

• Verify the gas cap is secure — a loose cap is a common, simple cause for a 2019 Lexus IS 300 illumination.
• Check for obvious driving changes: reduced power, stalling, or strange noises — these affect urgency.
• Use a diagnostic scan to capture stored trouble codes; this reveals whether it’s an emissions, misfire, sensor, or fuel delivery issue.
• If the light is flashing or severe symptoms appear, stop driving and bring the vehicle to our dealership immediately to avoid engine or catalytic damage.
• Warranty-covered repairs must be performed at a certified dealership to remain valid; our factory-trained techs preserve coverage and long-term value.

What does it mean when the check engine light comes on in a 2019 Lexus IS 300?

• It indicates the vehicle’s computer has detected a fault in emissions, engine management, or related systems. Codes identify the subsystem affected.
• Causes range from minor (loose gas cap, sensor fault) to serious (ignition misfires, catalytic converter efficiency loss).
• Ignoring codes can lead to reduced fuel economy, increased emissions, and costly downstream damage; dealer diagnosis isolates root cause quickly.
• Our technicians use OEM diagnostics and parts; repairs performed here often yield immediate savings by preventing repeat visits and long-term expense.
• Any repair covered under warranty must be completed at a certified dealership to maintain coverage and ensure proper parts and labor.

How much does a check engine light diagnostic cost for a 2019 Lexus IS 300?

• Diagnostic scan fees at our dealership are competitive and transparent; a standard scan typically ranges from $90–$150 depending on inspection depth.
• If the issue requires parts or extended diagnostics, we estimate costs before any repair so you can decide with confidence.
• Because we diagnose correctly the first time, customers often save money versus independent shops that may perform unnecessary repairs.
• Repairs covered by warranty must be performed at a certified dealership; using Nalley Lexus Roswell preserves coverage and avoids future out-of-pocket costs.
• Ask about current service specials and maintenance offers to maximize immediate and long-term savings.

What is the most common reason for check engine light on a 2019 Lexus IS 300?

• Common causes include oxygen sensor failure, ignition misfires from worn spark plugs or coils, catalytic converter efficiency issues, and fuel trim faults.
• Evaporative emissions leaks (loose or damaged gas cap) are frequent and easy to fix during the same visit.
• Misfires and sensor failures, if left unchecked, can damage the catalytic converter and raise repair costs significantly.
• Having Nalley Lexus Roswell address the issue provides immediate savings through accurate repair and long-term protection by preserving factory warranties.