VW Touareg Misfire: Rough Idle and Jerking Fixed

Having some experience with VW repairs, I encountered a similar issue with my 2013 VW Tiguan. The symptoms were nearly identical, rough idle and jerky acceleration, along with an illuminated check engine light. After diagnostic testing, it turned out to be a leak in the exhaust system affecting the oxygen sensor readings. This caused the engine management system to deliver incorrect fuel mixtures, leading to the rough running and acceleration issues. The fuel injectors were initially suspected, but they were working fine. The repair involved: Complete exhaust system inspection, Replacement of damaged exhaust components, New gaskets and mounting hardware, Clearing the error codes Total cost came to 265€, including parts and labor. The repair resolved all symptoms completely. To better assist with your case, could you share: Have you noticed any unusual exhaust noise? Which error codes are stored in the system? Does the rough idle get worse when the engine is warm? Have you had any recent exhaust work done? This information would help determine if your Touareg is experiencing the same underlying issue. The symptoms could also indicate ignition coil problems, which are common in VW engines of that era.

Had my latest service at 105000km and noticed these issues shortly after. The exhaust does make a slight rattling noise and the rough idle definitely gets worse when warm. Error codes show P0300 and P0303. The engine feels most unstable between 2000-3000 RPM. Started replacing spark plugs but wanted to get more input before spending money on other parts. Looking back at my maintenance records, the ignition coils have never been replaced. Could a failing crankshaft sensor also cause these symptoms? Want to avoid replacing fuel injectors if they are not the likely cause.

Thanks for providing those details. Your P0300 and P0303 codes definitely point toward engine misfire issues, which matches exactly what I experienced with my Tiguan. Given the symptoms and timing, I strongly suspect the ignition coils. After my exhaust system repair, I actually encountered similar issues again about 6 months later. The culprits turned out to be worn ignition coils and spark plugs. When I replaced them, the engine immediately ran smoother. The crankshaft sensor can cause misfires, but usually throws different error codes. My repair sequence: Changed all spark plugs, Replaced ignition coils, Cleared error codes, Test drove to verify fix Parts cost breakdown: Ignition coils: 180€, Spark plugs: 65€ The rattling exhaust should still be checked, as a faulty oxygen sensor or exhaust leak can contribute to rough running. But start with the ignition components since they commonly fail around 100000km in these engines. Would be interested to hear if replacing the remaining spark plugs and coils resolves your issue, as it did in my case.

Based on your diagnostic suggestions, I went ahead and replaced all ignition coils and spark plugs. The total cost was around 245€ but it was absolutely worth it. The engine now runs perfectly smooth with no misfires or jerking during acceleration. Those error codes are gone and the check engine light turned off after clearing the system. The slight exhaust rattle is still there, but since the engine performance is back to normal, I will have that checked during the next scheduled maintenance. Really glad I did not jump straight to replacing expensive components like fuel injectors or the crankshaft sensor. The oxygen sensor readings are now stable according to the scan tool, so the rough running was definitely caused by the failing ignition components. Makes sense given the mileage and that they were original parts. Will keep records of this repair to track when these parts might need replacement again in the future.