Audi S6 Starting Issues Point to Faulty Ignition Switch

Had a similar starting issue with my 2013 Audi S4 last year. As someone with basic car maintenance experience, I initially thought it was the ignition coil, but the problem turned out simpler. When the key turn failed to start the engine and dashboard lights were acting up, I took it to a workshop. They diagnosed a blown fuse in the ignition circuit. Total repair cost was 52 Euro, which covered diagnostics and fuse replacement. Before jumping to major repairs, checking the fuses is worth trying, it can save both time and money. The symptoms you describe could be related to various components though, ranging from simple fuse issues to more complex ignition switch problems. To provide more specific advice about your S6, could you share: Are there any specific dashboard light patterns when this occurs? Does the key turn smoothly in the ignition? Have you noticed any electrical issues with other systems? Did these starting issues begin suddenly or develop gradually? This information would help narrow down whether your case matches what I experienced or points to something different.

Last service was done at 81015 KM and I checked my car documentation, no fuses were replaced then. Good catch on checking fuses first. To answer your questions: dashboard lights work normally, key turns smoothly in the ignition switch, and no other electrical issues noticed. The starter motor seems to engage properly when it does turn. The problem developed over about 2 weeks, getting progressively worse. This makes me think its not a simple fuse issue like in your case. The car electronics seem fine otherwise, which points more toward either the ignition switch assembly or perhaps fuel delivery system. Think I will need to get it properly diagnosed at a workshop since the symptoms keep changing. What was the labor time for your repair? Trying to estimate how long I might need to leave the car at the shop.

Thanks for those details, definitely sounds different from my fuse issue since your electrical systems are working normally. The labor time for my simple fuse replacement was only about 30 minutes, but your situation likely needs more extensive diagnosis. With those symptoms, particularly the smooth key turn but inconsistent engine start and progressive worsening, I would suspect either the ignition switch assembly or possibly the fuel pump. On my S4, when the ignition switch eventually failed completely a year after the fuse incident, the repair took about 3-4 hours of labor time. The total cost was around 450 Euro including parts. Since your starting issue developed gradually rather than suddenly, and the engine runs rough when it does start, you might want to have them check the fuel system too. When they diagnosed my car, they ran a full system check that took about an hour. I would plan for the car to be at the shop for at least half a day to allow proper diagnosis and repair time. Worth mentioning to the workshop that you have already verified the fuses and electrical systems seem otherwise normal, this can help them focus their diagnostic process.

Thanks for this detailed feedback. Given the gradual onset and the fact that your ignition switch repair took 3-4 hours, I will plan to leave my car at the shop for a full day. Better to give them enough time for proper diagnosis and repair. Your experience with both the fuse and later ignition switch issues is really helpful. I will definitely mention to the workshop about the smooth key operation and normal electrical systems, plus how the problem developed over time. The 450 Euro cost reference gives me a reasonable baseline too, though I realize my repair might differ. Will book the car in next week and have them do a complete check of both the ignition system and fuel delivery. The rough running when the engine does start makes me think checking the fuel system is worth it, even if it costs a bit more in diagnostic time. Thanks again for sharing your repair experience, helped me understand what to expect and how to approach this with the workshop.