Frequently Asked Questions

What does it mean when the check engine light comes on in a 2015 BMW M4?

• It signals the vehicle’s onboard diagnostics have detected an emissions, fuel, ignition or sensor issue. It can range from a loose gas cap to a sensor or catalytic converter fault.
• At Nalley BMW of Decatur our factory-trained technicians use OEM diagnostics to identify the exact code and recommend the right repair, preserving long-term performance and resale value.
• We often cost less than independent shops when you factor in accurate diagnosis, genuine BMW parts and fewer repeat visits — delivering immediate and long-term savings.
• Repairs covered under warranty must be completed at a certified dealership to remain valid; we’ll confirm coverage and explain options.
• You can schedule service online or review our service specials before you visit.

How long does a check engine light service take?

• Diagnostic scans typically take 30–60 minutes. If parts or deeper inspection are needed, total time depends on the repair scope.
• Nalley BMW of Decatur emphasizes quick turnarounds with express bays and streamlined parts sourcing to get you back on the road sooner.
• We provide transparent estimates up front so you can decide, and we offer service financing to get repairs started today and pay over time.
• Check current service specials for savings that reduce immediate costs and long-term maintenance expense.

How much does a check engine light diagnostic cost for a 2015 BMW M4?

• Diagnostic pricing varies by issue, but our transparent pricing and bundled offers often deliver better value than independent shops because of accurate OEM diagnostics and fewer repeat visits.
• We’ll provide a clear estimate after the initial scan and explain options so you see the immediate and long-term savings of using dealership service.
• Remember: warranty-covered repairs must be performed at a certified dealership to preserve coverage; we’ll verify warranty status before work proceeds.
• To get an appointment, schedule service online and review current service specials.

What is the most common reason for check engine light on a 2015 BMW M4?

• Common causes include oxygen sensor faults, ignition coil or spark plug issues, and turbo or boost-related sensor faults on turbocharged engines.
• Left unaddressed, these can reduce fuel economy, increase emissions, and lead to costly repairs — dealership diagnosis helps avoid escalation.
• Nalley BMW of Decatur uses BMW-specific tools to pinpoint the exact code and recommend OEM repairs that preserve performance and warranty eligibility.
• We offer service financing so you can address problems promptly and save on long-term repair costs.

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

• Check the fuel cap is tight. If the cap is secure and the light stays on, bring the vehicle in for a diagnostic scan.
• Our certified technicians will run a full BMW diagnostic and explain findings in plain language, including repair timelines and cost-saving alternatives.
• We often deliver better overall value than independent shops because OEM diagnosis prevents misdiagnosis and repeat work.
• To get started, schedule service and check our service specials for available discounts.