redrocker55

There are a couple studies on these systems...one from AAA and one from Edmunds (among others). I feel both of them inflate the benefits. If you do the math on the AAA study a start/stop system will save 6.5% in fuel usage. That feels high to me unless you are in stop and go traffic to/from work.

According to the AAA study you would save $179 per year and according to the Edmunds study you would recoup the $300 average cost of these systems over 3 years...so about $100 per year in savings.

I drive mostly highway miles and not much stop and go/city traffic so my savings would be even less. But even at the quoted savings and the potential for higher wear/tear on the starter/ battery and potential inconvenience of downtimes it's just not worth it to me. So I will not be using the system in my car.

At these levels of efficiency...4,500 LB car with 450 HP and 4 wheel drive still getting 27 MPG is pretty amazing to me.

AAA?s Tests Reveal Real-World Benefits of Automatic Stop-Start Technology | AAA NewsRoom

Engine Stop-Start Systems Save Fuel at Low Cost

neddy191

Agree. I won't be using it.

Kris Hansen

The only times I didn't reach for the disable button was when I was at a traffic light, or stopped for any length of time. One OTHER thing to consider, when the engine is stopped, so too is the AC compressor (unlike some hybrids which often drive the AC with an electric motor.)

gk1

I am surprised to see this added to the S6 when it has not had it for 3 years. I guess that 1 extra MPG city makes a big difference in the overall CAFE numbers.

Kris Hansen

Stop start is less to do with MPG, and more to do with emissions. Reduces idling.

Dr Chill

Start/stop bites the weenie. Glad our 14 doesn't have it.

Kris Hansen

I don't mind it at stoplights, but hate it in traffic.

schalliol

I don't know that I want to add it to the 14, but since as far as I know the mechanicals are the same for pre-16 S6 as the 16, does anyone know if a button could be added to enable it? My assumption is that Audi just updated the software to enable it.

HyperS4

I gotta say, I was originally against this. However, the more I use it the more I appreciate it. You just have to learn to let go of the brake just enough to start the engine before you have to go, not right when you have to go. This takes away any hesitation. I can tell Im getting better gas mileage from using it.

schalliol

One more thought. I think the European S6 has start/stop in these model years. If someone wanted to add it to their 13-15 S6, could they? I don't know whether I'd use it, but having the button would be nice.