Audi A2 Fuel Injection Issues Killing Performance

Had almost the same symptoms on my 2006 Audi A3 1.4 petrol last winter. Having some experience with basic car maintenance, I first suspected fuel delivery problems based on the poor engine performance and high consumption. After taking it to my regular workshop, diagnostic tests revealed a faulty wiring connection to the fuel injection system. The main plug connecting to the engine control unit had corroded contacts, causing irregular fuel delivery and power loss. The fix was relatively straightforward, they cleaned the contacts and replaced the damaged connection assembly. Total cost was 95 Euro including diagnostics. The engine ran smoothly after that, fuel consumption went back to normal and the power issues disappeared completely. To help diagnose your case more accurately, could you share: Any error codes from diagnostics if available, When did these symptoms first appear, Does the engine behave differently when cold vs warm, Any unusual sounds from the engine bay, Have you noticed any fuel leak smells These details would help determine if your A2 is facing the same electrical connection issue or something different in the fuel system.

Last service was at 133000 KM, roughly 2500 KM ago. Thanks for the detailed response. The engine control light started flashing last week, and I noticed the symptoms getting progressively worse. The petrol engine runs particularly rough when cold, with more smoke visible during morning starts. No fuel smell detected, but there is a distinct ticking noise from the front of the engine that wasnt there before. I will get the error codes checked tomorrow, but your experience with the injection system wiring sounds very similar to what Im experiencing. The poor performance and high fuel consumption match exactly. Will check the connection points first before diving deeper into potential injector issues.

Based on those additional symptoms, especially the ticking noise and cold start issues, Im less convinced its just a wiring connection in your case. The rough cold running and progressive worsening of power suggests possible carbon buildup affecting the injection system. On my A3, when the wiring was faulty, the symptoms were more consistent regardless of engine temperature. The ticking noise you describe could indicate a partially blocked injector struggling to deliver proper fuel spray patterns. Before your next workshop visit, watch out for these signs I noticed with injection system problems: Uneven idle that smooths out as the engine warms up, Delayed throttle response, Black smoke specifically under heavy acceleration The high fuel consumption and reduced engine power could mean one or more injectors are stuck open, dumping excess fuel into the system. A proper injector cleaning service might be needed, which typically runs 150-300 Euro depending on the extent of carbon deposits. Get those error codes checked, my bet would be on fuel rail pressure or injector circuit codes rather than just connection issues like in my case.

Thanks for the information and I appreciate the thorough analysis. The symptoms match what you described perfectly, especially the uneven idle that improves with engine temperature. I checked this morning and noticed exactly that pattern. The ticking noise is definitely more prominent now and I can confirm the throttle response has become increasingly sluggish. The engine performance is at its worst during the first few minutes of operation, which aligns with your theory about carbon buildup affecting the injection system. Finally got the error codes read today: P0201 and P0203 showing injection circuit malfunctions. Given these codes and the symptoms, especially the excessive petrol consumption and power loss, I think youre right about the injectors being the culprit rather than just wiring. Will book it in for a full injection system cleaning and assessment. The quoted 300 Euro seems worth it to restore proper engine performance and reduce fuel consumption. Better to address this now before it causes more extensive damage.