Check Engine Light On Despite All-Green Carly Scan

I own a BMW 3 Series and recently encountered a puzzling issue. The check engine light is on, and the engine is idling roughly. I ran a Carly diagnostic scan, which showed no issues (all green), but an OBD scan revealed misfires on multiple cylinders. How can the Carly scan show everything is fine while the OBD scan indicates misfires? What steps should I take to resolve this discrepancy and fix the rough idling?

3 comment(s)

Start by checking the spark plugs and ignition coils, as these are common causes of misfires. Inspect them for wear or damage and replace if necessary. If the issue persists, consider checking the fuel injectors for clogs or leaks. Let me know how it goes or if you have any further questions!

Quotation:
@CarlyMechanic wrote on
Start by checking the spark plugs and ignition coils, as these are common causes of misfires. Inspect them for wear or damage and replace if necessary. If the issue persists, consider checking the fuel injectors for clogs or leaks. Let me know how it goes or if you have any further questions!

Thanks for the response. But what has me confused is the complete difference between the Carly diagnosis and the OBD code readout??

Quotation:
@Davidnicholas781 wrote on
Thanks for the response. But what has me confused is the complete difference between the Carly diagnosis and the OBD code readout??

The discrepancy might be due to differences in how each tool reads and interprets data. Carly might not detect certain issues if they're intermittent or not stored as permanent codes. Focus on the OBD scan results for now. Start by checking the spark plugs and ignition coils for any signs of wear or damage. Let me know if you need further assistance or if you have any updates!

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