Frequently Asked Questions

What is the most common reason for check engine light on a 2018 Volkswagen Passat?

• Common causes include oxygen sensor failures (P013x/P014x), catalytic efficiency codes (P0420), EVAP leaks (P044x), and misfires (P030x).
• Many issues begin as inexpensive sensor or seal repairs; delaying can escalate to expensive parts like catalytic converters.
• Our dealership often costs less than independent shops over time because certified diagnostics prevent repeat repairs and protect fuel economy.
• Remember: any repair covered under warranty must be performed at a certified dealership to preserve coverage.

What does it mean when the check engine light comes on in a 2018 Volkswagen Passat?

• The light signals a stored or pending OBD-II trouble code—anything from a loose gas cap to emissions or engine performance faults.
• It does not always mean immediate danger, but it does require timely diagnosis to prevent further damage and higher costs.
• Our technicians use factory-level scan tools to read specific codes and recommend OEM repairs that deliver long-term savings.
• If repair falls under warranty, it must be completed at a certified dealership to maintain coverage.

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

• Start with simple checks: gas cap seating, recent fueling, or visible leaks—these can trigger EVAP codes.
• If basic checks don’t clear the issue, bring the vehicle to our service center for a full scan and accurate diagnostics.
• Using Nalley Volkswagen of Alpharetta ensures OEM-level testing, factory software updates, and genuine parts for durable fixes.
• Warranty-covered repairs must be performed at a certified dealership to retain benefits and avoid out-of-pocket risk.

How much does a check engine light diagnostic cost for a 2018 Volkswagen Passat?

• Diagnostics at our dealership are competitively priced and often deliver lower total cost than independent shops through accurate diagnosis and OEM repairs.
• Typical scan-and-report fees vary, but finding the root cause quickly reduces unnecessary part replacements and repeat visits.
• Immediate savings come from precise troubleshooting; long-term savings come from OEM parts, correct repairs, and preserved warranty coverage.
• Any repair covered by warranty must be performed at a certified dealership to remain valid.

How long does a check engine light service take?

• Basic diagnostic scans and code reads often take 30–60 minutes; a full diagnosis can take 1–3 hours depending on symptoms and tests required.
• If parts replacement is needed, repair time depends on the component—simple sensors are faster, exhaust or catalytic work takes longer.
• We provide transparent estimates and schedule appointments to minimize downtime; use our Service Scheduler to book.
• For warranty repairs, completing work at our certified dealership ensures proper procedures and continued coverage.