VW Sharan TDI Engine Warning: System Readiness Alert

Recently went through something similar with a 2014 VW Touran TDI. As someone with moderate experience working on cars, I understand your concern about the system readiness monitors. The check engine light and error messages are often related to incomplete OBD readiness after disconnecting the battery or recent diagnostic scans. In my case, the workshop confirmed this was exactly the issue after a routine OBD2 reading. The solution was straightforward and cost nothing, just needed to complete a proper drive cycle to reset the system readiness monitors. This typically involves: Starting with a warm engine, Driving at steady highway speeds for 15-20 minutes, Including some city driving with stops and starts, Letting the car idle for a few minutes Before suggesting specific solutions though, could you share: What error messages are you seeing exactly? Has any recent work been done on the car? Have you disconnected the battery lately? What does the OBD scan show for incomplete monitors? This information would help determine if your issue is similar to what I experienced or if it might need deeper investigation of the exhaust system or other components.

Latest service was done at 89000km and showed no issues. The error messages are P0401 and P0406, both related to the EGR valve. Getting the onboard diagnostics done tomorrow at a local shop. Hopefully its just a sensor issue and not a complete EGR failure. After the vehicle inspection last month everything was fine, but now the engine runs a bit rough at idle. I did notice the exhaust sounds slightly different than usual, especially when cold. Anyone dealt with similar EGR codes on these engines? Would a computer reset and drive cycle help or is this likely a hardware problem?

Thanks for those details. Had almost identical EGR codes (P0401 and P0406) on my VW Touran TDI. While system readiness and drive cycles can sometimes resolve OBD issues, these specific codes typically point to actual EGR valve problems. In my case, the rough idle and exhaust sound changes were exactly the same symptoms. The onboard diagnostics confirmed what I suspected, the EGR valve was partially stuck due to carbon buildup. A computer reset and drive cycle did not fix the issue. The repair involved: Cleaning the EGR valve (initially tried), Eventually replacing the EGR valve (400€ parts + labor), Reprogramming the ECU, Completing a system readiness check After repair, all check engine codes cleared and the idle smoothed out completely. The exhaust sound returned to normal as well. Watch what your diagnostics show tomorrow, but be prepared that this might need physical repair rather than just electronic reset. These EGR issues are fairly common on our engines after 80000-90000km.

Thanks for that detailed info. After what you shared, I am fairly certain my issue is also EGR-related. The symptoms match exactly what you described, especially the rough idle and exhaust sound changes. I will get the car diagnostics done tomorrow as planned, but based on your experience, I should probably budget for an EGR valve replacement rather than hoping a simple drive cycle will fix it. The timing makes sense too since my car is around the same mileage where you had problems. Really helpful to know what the repair process involved. At least now I know what to expect and can make a more informed decision once I get the official diagnostic results. The 400€ cost reference is particularly useful for planning. Will update once I know more after the check engine codes are properly scanned at the shop.