Audi A1 Engine Misfires: Key Symptoms and Solutions

I had a very similar issue with my 2020 Audi A3 a few months back. Having some experience with basic maintenance, I first suspected spark plugs when the check engine light came on and the engine started running rough. The symptoms matched yours exactly, rough idle, jerking during acceleration, and reduced power. After a proper diagnosis, it turned out one fuel injector was faulty, causing cylinder misfire in cylinder 2. The fuel wasnt being delivered properly, which explained the performance issues. The workshop ran complete diagnostics and pressure tests on the fuel system, including the fuel pump and injectors. They confirmed the faulty injector was the culprit. Total repair cost was 515 Euro including parts and labor. Before suggesting specific solutions for your case, could you share: Does the rough running get worse when the engine is warm or cold? Have you noticed any unusual fuel consumption? Are there any specific RPM ranges where the problem is most noticeable? Can you share the specific error codes from the check engine light? This information would help determine if your A1 is facing the same injector issue or if its something else entirely.

Thanks for the feedback. I got my last service at 15000 KM and started noticing issues around 18778 KM. After reading your reply, I can confirm the engine misfiring gets worse when the car is warm, especially in the 2000-3000 RPM range. The throttle response feels inconsistent and jerky. The check engine light shows error P0303, suggesting a combustion misfire in cylinder 3. I checked the spark plugs and ignition coils visually, but everything looks clean. Fuel consumption has increased by about 15% compared to normal. The problem seems most pronounced during highway driving, particularly when trying to maintain steady speeds. Would it make sense to start by replacing the ignition coil in cylinder 3, or should I look into fuel injector testing first?

Having gone through this exact issue with my A3, your symptoms sound very familiar, but with a key difference. While my problem was a faulty fuel injector, your P0303 error code combined with the increased fuel consumption and specific RPM range issues suggests a failing ignition coil in cylinder 3. The check engine light triggering with error P0303 is a clear indicator of engine misfiring in that specific cylinder. The fact that it worsens with heat matches typical ignition coil failure patterns. In my experience, when fuel injectors fail, the symptoms tend to be more consistent regardless of engine temperature. Given the mileage since your last service and the specific symptoms, I would recommend: 1. Replace the ignition coil in cylinder 3 first, its a cheaper and simpler fix than fuel injector replacement 2. If the throttle response issues persist, then move on to fuel injector testing 3. Consider replacing all spark plugs while youre at it, even though they look clean My repair journey started with similar assumptions about fuel injectors, but learning from that, I would tackle the ignition system first in your case. The parts should cost around 85 Euro for a quality ignition coil, plus labor if you dont do it yourself.

Thanks all for the input. After getting your advice, I ordered a new ignition coil for cylinder 3 and had it installed yesterday. The rough idle and engine misfiring issues have completely disappeared, and the check engine light is now off. The repair was much more straightforward and cost-effective than I expected, total came to 115 Euro including labor. The mechanic confirmed the old ignition coil showed signs of heat damage, which explains why the combustion misfire got worse when the engine was warm. They also did a quick diagnostic check on the fuel injectors and fuel pump just to be safe, but everything tested normal. Fuel consumption has returned to normal levels and the engine runs smoothly across all RPM ranges now. Definitely glad I addressed this early before it could cause more serious engine damage. Going to keep monitoring for any changes, but so far the car runs like new again.