Frequently Asked Questions

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

• Check for obvious issues first: loose or missing gas cap, recent fueling, or visible fluid leaks.
• Note symptoms — drivability changes, noises, or warning lights — before you visit the shop to speed diagnosis.
• Bring your 2018 Lexus IS 300 to Nalley Lexus Roswell for a fast scan; our factory-trained technicians prioritize accurate diagnosis to prevent unnecessary repairs.
• Using our certified service often costs less than independent shops in the long run because we identify root causes quickly and protect factory warranties.

What is the most common reason for check engine light on a 2018 Lexus IS 300?

• Common causes include oxygen sensor failures, loose gas caps, evaporative system leaks, misfires, or catalytic converter efficiency issues.
• Symptoms vary from no change in drivability to rough idle, poor fuel economy, or reduced power.
• At Nalley Lexus Roswell we use OEM-grade diagnostics to pinpoint the cause and recommend economical repairs that protect vehicle value and warranty coverage.
• Repairs performed at a certified dealership ensure warranty compliance and often deliver immediate and long-term savings versus repeated fixes elsewhere.

How much does a check engine light diagnostic cost for a 2018 Lexus IS 300?

• Diagnostic scan fees typically range from a complimentary quick scan to a modest diagnostic charge for in-depth testing; exact pricing depends on needed tests.
• Many issues are identified quickly; when further testing or parts are required we provide transparent estimates before work begins.
• Nalley Lexus Roswell often costs less than independent shops overall because our accurate diagnostics prevent unnecessary repairs and protect long-term reliability.
• Remember: repairs covered under warranty must be completed at a certified dealership to preserve coverage and maximize savings.

What does it mean when the check engine light comes on in a 2018 Lexus IS 300?

• The check engine light signals that the vehicle’s on-board diagnostics detected a system fault — anything from an emissions sensor to an engine misfire.
• Some faults are minor and safe to drive on briefly; others can indicate imminent damage or safety risks.
• Bring your 2018 Lexus IS 300 to Nalley Lexus Roswell for prompt evaluation so factory-trained technicians can recommend the most cost-effective, warranty-compliant repairs.
• Our dealership emphasizes immediate and long-term savings by pairing accurate diagnosis with genuine parts and certified service.

How long does a check engine light service take?

• A basic scan and report can take 15–45 minutes; comprehensive diagnostics and repairs vary from one to several hours depending on complexity.
• Minor fixes like tightening a gas cap or replacing a sensor are often same-day services; larger repairs require an estimate and scheduling.
• Nalley Lexus Roswell offers efficient service scheduling and transparent timelines, and our factory-trained technicians work to minimize downtime while maintaining quality.
• Because we perform warranty-compliant repairs with OEM parts, you get long-term value and fewer return visits compared with incomplete fixes elsewhere.