VW Suran Engine Misfire: Rough Idle and Loss of Power

Having dealt with similar issues on my VW Golf 2011, I can relate to your problem. I have some experience with fuel system problems and the symptoms you describe match what I encountered. The cylinder misfire and rough idle turned out to be caused by a faulty fuel injector in my case. The throttle response was terrible, and the engine would stumble especially during acceleration. After diagnosing the issue, my workshop found that one fuel injector was not spraying properly, leading to incomplete combustion. The repair involved: Diagnostic testing to confirm the faulty injector, Removing and replacing the defective fuel injector, Cleaning the fuel injection system, Basic recalibration Total cost was 515€ including parts and labor. Before suggesting specific solutions, it would help to know: Have you had the diagnostic codes read? What maintenance has been done recently? Does the problem get worse when the engine is cold or hot? Are you noticing any unusual fuel consumption? Have you checked your spark plugs recently? This information would help determine if your issue is similar to what I experienced or if it might be something else.

Thanks for the detailed explanation. After reading the codes at my local workshop, they found cylinder 2 had a combustion misfire. Changed all spark plugs since they were original (81893km), but the check engine light came back on after a few days. The mechanic now suspects a failing ignition coil might be the root cause, as the misfire symptoms persist even with new plugs. They recommended replacing the coil pack for that cylinder. My only concern is whether I should replace all ignition coils while at it, given the age and mileage of the car. The cylinder misfire is definitely more noticeable during cold starts and when accelerating. Fuel consumption has increased by about 15% since these issues started.

Based on what you shared about the persisting misfire after changing spark plugs, your mechanic is on the right track. In my VW Golf, I initially only replaced the coil pack for the misfiring cylinder, but within 6 months, another coil failed. Given our cars age and mileage, replacing all coils is a smart preventive measure. After changing all ignition coils, my combustion misfire issues were completely resolved. The check engine light stayed off, and the rough running disappeared. Fuel consumption returned to normal, and that annoying jerking during acceleration was gone. The full set of coils cost 280€, plus 90€ labor. While it seems expensive upfront, its cheaper than multiple visits for individual coil replacements. Just ensure you get OEM or high-quality aftermarket coils, cheap ones tend to fail prematurely. One tip: while the coils are being replaced, have them inspect the fuel injector connectors and wiring. In some cases, damaged wiring can cause similar symptoms, and its best to catch any potential issues while everything is apart. Remember to clear the engine codes after replacement to ensure any new check engine light is actually indicating a new problem rather than the old fault.

Thanks for the advice. I decided to follow the suggestions and replaced all ignition coils, not just the faulty one. The total cost came to 370€ but it was worth it. After the repair, the engine misfiring symptoms completely disappeared and the car runs smoothly again. No more jerking during acceleration and the check engine light has stayed off. The fuel consumption is back to normal levels and cold starts are much smoother now. My mechanic also checked the fuel injectors and wiring while doing the work, everything looked good there. Really glad I addressed all the coils at once rather than waiting for them to fail one by one. For anyone else facing similar issues with engine misfiring on high-mileage cars, checking both spark plugs and ignition coils is definitely the way to go. The investment in quality parts pays off in the long run.