Q3 Rough Idle & Stalling Points to Fuel System Issues

As an A3 2020 owner, I experienced nearly identical symptoms last season. The jerking during acceleration combined with rough idle strongly points to a fuel delivery issue. In my case, the fuel pump was failing intermittently, causing inconsistent fuel pressure and triggering the check engine light. The symptoms you describe match a few potential issues: Failing fuel pump, Clogged fuel filter, Loose fuel system connections, Engine misfire due to faulty fuel pressure sensor My repair required fuel pump replacement after diagnostic tests confirmed irregular fuel pressure readings. This was a serious repair that needed immediate attention, as continued driving could have led to complete fuel system failure or engine damage. Before replacing major components, have a technician: 1. Check fuel pressure readings 2. Inspect electrical connections to the fuel pump 3. Scan for specific error codes 4. Test the fuel pressure sensor The irregular engine performance combined with the check engine light warrants professional diagnosis rather than parts swapping. These symptoms often indicate fuel system problems that can worsen if not properly addressed.

Thanks for the detailed breakdown of the fuel system issue. Your symptoms do sound exactly like what I faced with my Q3 a while back. The rough idle and engine stalling ended up being a combination of clogged fuel injectors and a worn fuel pressure sensor. Did you track the repair costs for your fuel pump replacement? Also curious if youve had any engine misfire issues since the repair was done? My fuel economy actually improved quite a bit after getting everything sorted.

Thanks for asking about the follow-up. Actually, I ended up not needing the full fuel pump replacement. The mechanic found the fuel pressure sensor was defective, causing the rough idle and inconsistent fuel delivery. They fixed a faulty cable connection which was the root cause, total repair cost was 95 Euro. Since the repair, my fuel economy has improved noticeably and the engine runs perfectly smooth. No more misfires or jerking during acceleration. The fuel system is working exactly as it should now. Getting that sensor and connection fixed made a huge difference in overall performance. This experience really showed how a relatively simple fuel system issue can mimic more serious problems. The rough idle completely disappeared after the repair. Just goes to show proper diagnosis is crucial rather than jumping straight to major component replacement.

Thanks for all the helpful feedback. I finally got my Q3 checked out yesterday after putting it off. The mechanic ran a full diagnostic and found the fuel pressure sensor was failing, along with some clogged injectors. Total repair came to 450 Euro including parts and labor. The rough idle and stalling issues are completely gone now. The engine runs smooth and the check engine light finally cleared. My fuel economy has already improved by about 15% on my daily drives. No more jerking during acceleration either. The mechanic showed me the old parts, the fuel injectors were pretty gunked up and the sensor had definitely seen better days. Really glad I got it sorted before any serious fuel system damage occurred. Lesson learned about not waiting too long when these symptoms first appear.