Hi there, I have a 2018 S4 B9, owned it 2 years at the end of this month. No issues, other than a faulty wing mirror heater, done under warranty last November. I do a lot of miles at the moment commuting, upon average 100 per day. Today, from a cold start (in inclement weather) I drove 25 miles - not hard miles, just a sedate drive in D mode. After 20 miles I realised that the stop/start system wasn’t working and there appeared to be a very loud hum coming from the engine. However, there was an artic in front of me and I thought it might be that. When the artic turned off and the hum continued I pulled over and manually disengaged the ignition. Usually when I do this, the car stops and all noises (apart from quite a quiet fan) cease. Today the car continued humming and slowly wound itself down, it sounded a bit like a jet engine or a helicopter. The noise didn’t happen again on that journey, but the start/stop still wouldn’t engage - FYI the ac wasn’t running particularly fast, cold or hot, it was on number 2 fan @ 19 degrees. I went about my business for about an hour, returned to the car, no noise and s/s system operational once again. Drove another 25 miles without issue. Called Audi and booked it in to be looked at, but they have no availability until the 15th. I wasn’t too fussed as it seemed to have stopped anyway. However, this evening I popped out for a relatively short journey of 8 miles and it happened again. Temperature is fine, not any different to usual.
Any ideas?
I filmed it for the audio, here is a link to youtube -
Any ideas?
I filmed it for the audio, here is a link to youtube -
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