VW Touran Diesel Injector Issues & Performance Fixes

As someone with moderate repair experience, I dealt with nearly identical symptoms on my 2006 VW Passat Diesel. The issues started with rough idling and eventually led to significant power loss and increased fuel consumption. My workshop performed a thorough diagnostic process that revealed dirty injection valves were causing the misfire and poor engine performance. They ran specific tests to measure injection timing and fuel pressure, confirming that inconsistent fuel delivery was the root cause. The repair involved: Complete injector cleaning and testing, Replacing seals and connectors, Calibrating the injection system, Full emissions system check Total cost came to 515€ and resolved all symptoms. The engine ran smoothly after the repair, fuel economy improved dramatically, and power was fully restored. To provide more specific advice for your Touran: What engine size do you have? Are you getting any specific error codes? How many kilometers since the last fuel filter change? Does the problem get worse in cold weather? These details would help determine if your vehicle is experiencing the same injection system issues I encountered.

Last service was performed at 90043km, and I am experiencing exactly the symptoms you described. The engine starts better now after the fuel filter change, but still having performance issues. My engine is a 1.9L TDI. The check engine light shows P0401 code related to the EGR system. The clogging seems worse during cold starts, suggesting a possible connection between the injection system and emissions components. The vehicle runs smoother at higher RPMs, but the power loss is still noticeable when accelerating. Would you recommend checking the EGR valve before proceeding with injector work, or should both systems be inspected simultaneously?

Based on our similar experiences, I strongly recommend having both the EGR and injection system checked together. After my injector repair, I discovered that clogging in the EGR system was contributing to my engine performance issues as well. The P0401 code often indicates restricted EGR flow, which can work hand in hand with dirty injectors to reduce engine performance. The cold start issues you mention are classic symptoms of this combination problem. For reference, after my initial injector service, I had the EGR valve cleaned and tested for about 180€. The complete solution included: EGR valve cleaning and flow testing, Intake manifold inspection for carbon buildup, Verification of proper EGR operation, System-wide diagnostic scan The combined repair of both injection and EGR systems completely resolved the power loss and rough running issues. In my case, addressing just the injectors provided only partial improvement, similar to what you are experiencing after the fuel filter change. Since your symptoms match my experience so closely, I would suggest having your repair shop examine both systems. This approach might cost more initially but could prevent repeat repair visits and continued engine performance problems.

Thank you for sharing your detailed repair experience. Given these insights, I will schedule a complete diagnostic check focusing on both the EGR and injection systems. Your repair timeline matches my issues perfectly, and the combined approach makes sense to avoid multiple workshop visits. The cold start problems and power loss are becoming more noticeable, so I will have this addressed soon. My diesel engine symptoms truly mirror what you experienced, especially regarding the rough idle and performance issues improving at higher RPMs. One final question, did you notice any black exhaust smoke or excessive emissions before your repair? I am seeing some dark smoke during acceleration, which seems consistent with the injection system problems you described. I appreciate the comprehensive breakdown of costs and repair steps. It helps set realistic expectations for the work needed to restore proper engine performance. Will book an appointment this week and request they check both systems as you suggested.