A6 EGR Failure Causes Smoking and Power Loss Issues

Recently had similar issues with my 2016 Audi A4 and can confirm these symptoms match a faulty EGR valve. The automotive repair involved removing and cleaning the EGR valve first, but it turned out the valve was completely stuck open, causing excessive exhaust gas recirculation. The repair required complete EGR valve replacement since cleaning didnt resolve the vacuum leak. The symptoms matched exactly, power loss, rough idle, excessive fuel consumption, and that distinct hissing sound during acceleration. This was a serious issue requiring immediate attention, as continuous operation with a faulty EGR valve can damage the engine and definitely cause emissions test failure. The repair also included cleaning the intake manifold, as the stuck valve had allowed carbon buildup. The fix completely resolved all symptoms, restored proper power delivery, eliminated smoke, normalized fuel consumption, and cleared the check engine light. Most importantly, the car passed the emissions test after the repair. Worth noting that postponing EGR valve replacement often leads to more extensive engine problems and higher repair costs down the line.

Thanks for sharing your A4 experience. Glad it worked out with the EGR valve replacement. Dealing with rough idle and vehicle emissions problems on my A6 right now too. Currently choosing between two shops for fixing the recirculation system. Did your diesel engine performance get back to normal right after the fix? And can you share what the total repair cost was? Just wondering if any other related issues popped up since the work was done.

Wanted to update that I took my A4 to a trusted mechanic who diagnosed and fixed the exhaust gas recirculation system. The total came to 355 Euro for replacing the defective EGR valve. Engine performance returned to normal immediately after the repair. The rough idle disappeared completely, and the check engine light cleared once the new valve was installed. Fuel consumption dropped back to normal levels within the first tank. Its been several months since the fix, and no other issues have emerged. Just to clarify though, mine is actually a gasoline engine, not diesel. The automotive repair shop explained that EGR problems are common in both fuel types. They also performed a thorough inspection of related components while fixing the vacuum leak. The catalytic converter and surrounding parts were all in good condition, which helped keep the repair costs focused just on the EGR valve replacement. If youre still choosing between shops, make sure they specialize in German performance vehicles since proper diagnostic equipment is essential for these recirculation system repairs.

Finally got the EGR valve situation sorted on my A6. After getting recommendations, I took it to the performance shop across town. They ran complete diagnostics and confirmed what we suspected, a failed EGR valve causing those emissions problems and the rough idle. The repair cost came to 420 Euro including parts and labor. They showed me the old valve which was completely gunked up and stuck. The check engine light disappeared right after they installed the new one. Best part is the engine feels strong again with no more jerking or hissing during acceleration. Took it for an emissions test yesterday just to be sure, passed with flying colors. Fuel consumption is back to normal too. Really glad I addressed this before it caused more engine damage. The automotive repair shop did great work and even gave the intake a proper cleaning while they were in there. Thanks again for the helpful advice about getting it fixed promptly. The symptoms matched exactly what you described and choosing a shop that knows these engines made all the difference.