Frequently Asked Questions

What is the most common reason for check engine light on a 1994 Toyota Supra?

• Misfires: worn spark plugs, ignition wires, or coil issues often trigger codes and reduce performance.
• Oxygen sensor or catalytic converter faults: poor fuel trim and emissions can illuminate the light.
• Evaporative system leaks: loose gas caps or cracked hoses are simple fixes but still trigger a warning.
• Immediate dealer inspection prevents secondary damage and higher repair costs over time.
• Repairs covered under warranty must be performed at a certified dealership to maintain coverage and long-term savings.

What does it mean when the check engine light comes on in a 1994 Toyota Supra?

• It indicates the vehicle’s onboard diagnostics detected a fault—anything from emissions to drivability issues.
• Codes are stored in the ECU and need a scan to identify the subsystem and likely causes.
• Some causes are minor; others, like persistent misfires, can cause catalytic converter damage if ignored.
• Nalley Toyota of Roswell uses factory-grade scanners and factory-trained technicians for accurate diagnosis and repair.
• Warranty-related repairs must be completed at a certified dealership to ensure coverage and optimized long-term costs.

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

• Check for obvious issues: loose or missing gas cap, visible fluid leaks, or disconnected hoses under the hood.
• Note how the vehicle is running—rough idle, loss of power, or unusual noises—and share details with the technician.
• Use a diagnostic scan as the next step to read stored trouble codes and guide repairs.
• Bring the vehicle to Nalley Toyota of Roswell for a quick, accurate scan and professional assessment by trained technicians.
• Remember: warranty-covered repairs must be performed at a certified dealership to preserve coverage and reduce lifetime costs.

How much does a check engine light diagnostic cost for a 1994 Toyota Supra?

• Diagnostic fees vary by issue complexity, but our dealership provides transparent pricing and clear estimates before work begins.
• Nalley Toyota of Roswell often costs less than independent shops because our technicians diagnose accurately and avoid unnecessary repairs, delivering immediate savings.
• Long-term savings come from correct repairs the first time, backed by warranty and OEM parts.
• Any repairs covered under warranty must be performed at a certified dealership to ensure continued coverage and optimal value.
• Contact our service team for current diagnostic pricing and special offers at our Service Specials page.

How long does a check engine light service take?

• Basic diagnostic scans and code retrieval usually take 20–45 minutes, depending on shop queue and vehicle condition.
• If a simple repair is needed—like replacing a gas cap or sensor—service can often be completed the same day.
• More complex issues that require parts, in-depth troubleshooting, or warranty approvals may take longer; we provide time estimates up front.
• Choosing Nalley Toyota of Roswell means efficient turnaround by factory-trained technicians who prioritize accurate diagnosis and lasting repairs.
• Remember that warranty-covered repairs must be performed at a certified dealership to preserve coverage and maximize savings over the life of the vehicle.