Frequently Asked Questions

What is the most common reason for check engine light on a 2004 Toyota Camry?

• Loose or damaged gas cap causing evaporative emissions (EVAP) faults, a frequent low-cost issue to correct.
• Faulty oxygen sensors (O2) or catalytic converter efficiency codes that can reduce fuel economy and raise emissions.
• Engine misfires from ignition or fuel system faults, which can damage the catalytic converter if left unfixed.
• Our certified technicians identify root causes with factory-grade diagnostic tools to minimize repeat visits and long-term cost.
• Repairs covered under warranty must be performed at a certified dealership — we handle warranty work promptly to protect your coverage.

What does it mean when the check engine light comes on in a 2004 Toyota Camry?

• It signals the powertrain control module detected a fault in emissions, ignition, fuel delivery, or related systems.
• Severity ranges from minor (loose cap, sensor) to urgent (engine misfire, overheating); diagnostics determine priority.
• Our scans give a clear diagnosis and estimate so you know immediate and long-term costs before authorizing repairs.
• Nalley Toyota of Roswell often costs less than independent shops while delivering factory-trained technicians and OEM parts.
• Warranty repairs must be completed at a certified dealership to maintain coverage; we perform those repairs correctly and efficiently.

How long does a check engine light service take?

• Diagnostic scans typically take 30–60 minutes to read codes and run basic system checks.
• Simple repairs (gas cap, sensor replacement) can often be completed the same day; more complex repairs require scheduling and parts.
• We provide realistic time estimates up front and prioritize safety—urgent issues like active misfires may require immediate attention.
• Using our dealership can save time across the repair lifecycle due to OEM parts availability and factory-trained technicians.
• For warranty-covered repairs, work must be done at a certified dealership to ensure proper documentation and coverage continuity.

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

• Check that the gas cap is tight and undamaged—an easy fix that resolves many EVAP-related codes.
• Note vehicle behavior: rough idle, loss of power, or a flashing light indicate higher urgency.
• Bring the vehicle to Nalley Toyota of Roswell for a diagnostic scan to read stored codes and clear false alerts if appropriate.
• We explain immediate and long-term savings by addressing root causes with OEM parts and factory-trained technicians.
• If the repair is covered by warranty, have it done here to protect your benefits and ensure correct repairs.

How much does a check engine light diagnostic cost for a 2004 Toyota Camry?

• Diagnostic fees vary, but our dealership provides transparent pricing and a clear estimate after the scan.
• Many diagnostics are competitively priced — Nalley Toyota of Roswell often costs less than independent shops while delivering higher service standards.
• Addressing problems promptly can avoid larger expenses: small sensor fixes prevent catalytic converter or engine damage later.
• We outline immediate and long-term savings so you can make informed repair decisions with OEM parts and factory-trained techs.
• Remember, warranty-covered diagnostics and repairs must be completed at a certified dealership to maintain coverage and protection.