VW Up Engine Misfiring: Causes and Solutions Revealed

I had a similar issue with my 2018 VW Polo TSI. I have some experience working on cars, mainly basic maintenance, but this issue required professional help. The symptoms you describe match exactly what I experienced, poor throttle response, combustion misfire, and the check engine light came on. Initially, I thought it might be spark plugs or an ignition coil issue, but after diagnosis, it turned out to be a faulty fuel injector. The workshop did a complete diagnostic scan and pressure test of the fuel system. They found one injector was not delivering fuel properly, causing the engine to run rough and misfire. The repair involved replacing the defective injector, which came to 515€ including parts, labor, and testing. The car has been running perfectly since the repair, smooth acceleration, no more jerking, and the check engine light cleared up immediately. Before offering more specific advice, could you share: How many kilometers/miles are on your Up? Have you noticed any fuel consumption changes? Does the problem get worse when the engine is cold or warm? Have you had any recent maintenance work done? This information would help determine if your issue is similar to what I experienced or potentially something different.

Thanks for sharing your experience. After my last service at 30000km, everything was fine until last week. The workshop checked for error codes and found cylinder misfire codes. They confirmed two ignition coils were failing, causing the rough running and check engine light. The repair cost was 280€ including parts and labor for replacing both ignition coils and all spark plugs as preventive maintenance. The car now runs perfectly smooth with no jerking during acceleration. For anyone having similar issues, the combustion misfire symptoms cleared immediately after the repair.

Thanks for the update about your ignition coil issue. That 280€ repair cost was actually quite reasonable considering they replaced both coils and all spark plugs. My fuel injector replacement was significantly more expensive at 515€. What you experienced with the rough idle and combustion misfire is a classic symptom of failing ignition coils. Its good your workshop took the preventive approach by changing all spark plugs at the same time. This often helps prevent similar issues from occurring with the remaining coils in the near future. After my fuel injector repair, I learned its worth checking for these common causes of misfires in order of likelihood and repair cost: 1. Spark plugs 2. Ignition coils 3. Fuel injectors The throttle response improvement you mentioned after the repair is exactly what I experienced once my fuel injector was replaced. Its amazing how quickly these issues clear up once the root cause is fixed. Have you noticed any improvement in fuel consumption since the repair? When my injector was failing, I saw significantly worse fuel economy until it was fixed.

Thanks for asking about the fuel consumption. Yes, I have noticed about 10% better fuel economy since the ignition coil and spark plug replacement. The workshop explained that failing ignition coils can cause incomplete fuel combustion, which wastes fuel and causes the check engine light to activate. For anyone searching the forum with similar symptoms, here is a quick summary of my experience: Rough running engine with jerking during acceleration, Check engine light came on, Diagnostic scan revealed cylinder misfire codes, Two faulty ignition coils identified, 280€ repair included new coils and spark plugs, Problem resolved immediately after repair, Fuel economy improved after fix The preventive spark plug replacement made sense since they were due for replacement anyway. Much better to fix everything at once than risk another cylinder misfire down the road.