VW Polo Engine Misfire Points to Bad Ignition Coils

I had a very similar issue with my 2006 VW Golf 1.4 TSI last spring. As someone with basic car maintenance experience, those symptoms immediately made me think of coil pack problems too. The engine was misfiring and stalling at idle, exactly like yours. After some hesitation during acceleration, the check engine light came on. The symptoms you describe match my experience perfectly. Took it to my regular workshop where they diagnosed a faulty connection in the wiring harness going to one of the ignition coils. The cable insulation had worn through, causing intermittent connection issues. Total repair cost was 95€ including diagnostics and fixing the wiring. Before suggesting specific fixes for your Polo, could you share: Have you checked for any error codes? Does the misfire happen more when the engine is cold or warm? Are all cylinders affected or does it feel like just one is misfiring? Has the car been serviced recently? This information would help determine if your issue is similar to what I experienced or if you might be dealing with a different type of coil failure altogether.

Just reached 34904km on the odometer. Pulled the codes with a basic scanner and got P0301, indicating cylinder 1 misfire. The issue seems worse when the engine is cold and improves slightly after warming up. Definitely feels like a single cylinder problem rather than all of them. The rough running is most noticeable at idle, where the engine occasionally stalls. When accelerating, the check engine light starts flashing. Looking at the spark plugs might make sense since they havent been changed since the last service about 8 months ago. The symptoms do sound similar to your coil pack issue. Seems like checking the wiring harness for wear would be a good first step before replacing parts. Did you notice any visual damage to the cables before taking it to the shop?

Thanks for the additional details. Your symptoms are even more similar to what I experienced than I initially thought. The P0301 code is exactly what my Golf showed, and like yours, the misfire was definitely worse during cold starts. The flashing check engine light during acceleration is a classic sign of ignition system problems. In my case, the damaged wiring was not immediately visible, it was hidden under the ignition coil housing. The mechanic found it only after removing the coil pack from cylinder 1. Since youre getting the same error code and similar cold-start symptoms, Id bet your ignition coil issue is nearly identical. However, theres a key difference, my problem was wiring related, but your mileage and timing suggest it could be the actual coil failing. The 8-month-old spark plugs are probably fine, though checking them is never a bad idea. Before you start replacing parts, do this quick test that helped diagnose my issue: Try swapping the ignition coils between cylinders 1 and 2. If the misfire moves to cylinder 2 (showing P0302 instead), you can be confident its a faulty coil rather than wiring or spark plugs. This saved me from unnecessarily replacing parts when I had my engine hesitation problems.

Thanks for clarifying those points about swapping coils between cylinders. I decided to try your diagnostic suggestion before spending money on new parts. Swapped the coils between cylinders 1 and 2, and the misfire code changed to P0302, exactly like you predicted. The check engine light followed the coil to the new cylinder. After confirming the faulty ignition coil, I inspected the wiring harness but found no visible damage or wear. Seems like my issue is just the coil itself rather than the wiring problem you experienced. The spark plugs also looked normal when I checked them during the coil swap. Going to order a new ignition coil since the diagnostic test clearly showed thats the failing component. Much better knowing exactly whats wrong before visiting the workshop. Really appreciate the advice about the cylinder swap test, saved me from blindly replacing multiple parts trying to fix the engine misfire.