Frequently Asked Questions

How much does a check engine light diagnostic cost for a 2018 Toyota Avalon Hybrid?

• Diagnostics at Nalley Toyota of Roswell start with a computerized scan to read stored trouble codes and a technician inspection to interpret results.
• We often offer prices that compare favorably to independent shops while delivering factory-trained technicians, genuine Toyota parts, and transparent estimates.
• Immediate savings come from accurate diagnosis and targeted repairs; long-term savings come from preventing cascading damage (for example, misfires that damage the catalytic converter).
• Any repairs covered under warranty must be performed at a certified dealership to retain coverage and ensure proper parts and procedures.

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

• Start with the basics: secure the gas cap. A loose or damaged cap is a common cause of an EVAP code and can often extinguish the light after tightening and a few drive cycles.
• Note vehicle behavior — rough idle, stalls, reduced power or unusual noises — and record recent fueling or maintenance events to share with our technicians.
• If the light is flashing or performance is impaired, stop driving and contact Nalley Toyota of Roswell immediately to avoid further damage.
• For warranty claims or complex repairs, bring the vehicle to our certified service team so covered repairs are performed correctly and your warranty remains intact.

What does it mean when the check engine light comes on in a 2018 Toyota Avalon Hybrid?

• The light indicates the vehicle’s onboard computer has detected an emissions, engine, or drivetrain fault that needs attention.
• Codes range from simple issues like a loose gas cap or sensor fault to urgent problems such as misfires or emissions system failures.
• Early diagnosis at Nalley Toyota of Roswell reduces repair costs and helps preserve fuel economy, reliability, and resale value.
• Warranty-covered items must be repaired at a certified dealership to ensure the correct parts and documented service history.

How long does a check engine light service take?

• Routine diagnostics typically take 30–90 minutes, depending on code complexity and inspection needs.
• Simple fixes, such as a sensor replacement or tightening a component, can be completed the same day in many cases.
• If a repair requires parts or in-depth diagnostics, our team will provide a clear timeline and estimate so you can plan accordingly.
• Using our certified technicians often shortens repair time overall: accurate diagnosis avoids repeat visits and minimizes long-term downtime and cost.