How much fuel does ASS (Auto Start Stop) save?

[AmericanPatriot100]

I have a manual and when I stop to park I usually put it in neutral pull the parking brake and then it auto stops cause I forgot to turn off ASS. Instead of letting it auto start again just to turn it off. I just turn the jeep fully off. Hopefully this doesn’t cause more damage because the ASS wasn’t able to complete its fully duty cycle.

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[3TV]

The traffic flow must be much lighter where I live, because it is very rare to sit at a traffic light long enough to make a difference. My studies were much more scientific and precise than his, and for my average time with the engine off due to ASS of 3.6 seconds, I calculate that the ASS system in my 2.0 JLR would save 1 quart of fuel over the lifespan of the starter motor.

 

[SmokyMtnsJeepGirl]

I hate the ESS. I turn it off every time I start it. I found I actually get a bit better gas mileage. And I hate that the AC and heat don't maintain their temp with ESS on - it's hot as hades in the summer down South, and the last thing I want is no AC. If I could disable the ESS permanently, I would.

 

[AmericanPatriot100]

If I was at all concerned about the fuel mileage I would have not traded in my civic that got 45mpg. Or have an Escalade with a 6.2L V8. Or gotten a Jeep. The fact is that the ASS is annoying if you forget to turn it off. I never had a vehicle with it previously and haven’t had the jeep long enough to always remember to turn it off. My trip to the highway is 1.1miles and has no stop light or stop signs so I’m always forgetting it’s on until I get into the city at that first red light and the jeep shuts off and freaks me out. And I immediately hit the ASS off button and it starts right back up. I’m worried that not letting it run its full duty cycle will cause more damage in the long run.

 

[2nd 392]

The traffic flow must be much lighter where I live, because it is very rare to sit at a traffic light long enough to make a difference. My studies were much more scientific and precise than his, and for my average time with the engine off due to ASS of 3.6 seconds, I calculate that the ASS system in my 2.0 JLR would save 1 quart of fuel over the lifespan of the starter motor.

The uhh, starter lifespan with or without using ASS ?

 

[Dusty Dude]

The bigger hidden issue isn’t just starter wear. It’s starting an engine with zero oil pressure while it is under load.

 

[Jeep Wick]

It's a bit surprising how much it saves. City driving, of course. And he doesn't take additional wear into consideration.

Call it 6%... For most of us that is less than 1 mpg. You can easily do better by simply changing your driving style.

 

[Thane]

Engineering Everything ignoring the initial cost of the ESS system and continuing maintenance costs.

You could never make back the costs, under any driving conditions.

Even using his stated 4-8% mpg (6% avg) savings using California fuel pricing $4.50/gal and average 12K miles per year

12,000 miles/20mpg= 600 gal @ $4.50/gal=$2,700 ESS saving 6%=$162 per year.
The Mopar battery alone lists for $180 plus tech time to replace, and initial cost of system. The cost of E-Torque??? thousands.

 

[calemasters]

How much fuel does ASS (Auto Start Stop) save?

In the past 62,000 miles, auto stop start has saved me approximately 15 oz. of diesel fuel. It almost always displays "Auto Stop Start Not Ready" or "Battery Charging".

 

[MayThe4x4BWU]

5 pages of conversations about ASS and not one humorous post...boring

 

[Wbino]

Most guys know that ASS will never save you money in fact it will cost you plenty, including some heartache. (And headaches).

 

[3TV]

The uhh, starter lifespan with or without using ASS ?

With using it. My study has not yet concluded on the lifespan of the starter without using ASS.

 

[Ratbert]

I’ll admit it. I didn’t watch it.

But why show what people thought it would take to be beneficial based on a survey instead of showing what it actually could save? Did they mention who they surveyed? Was it mechanics, environmentalists, or a car full of nuns?

It was simply showing how far off from reality our (Americans') estimates of ASS usefulness were. It showed the estimates, then showed reality.

I'm sure we've spent much longer trying to correct misunderstandings about what the video actually said to people that didn't watch it than it would have taken them to simply watch it, but that's our reality.

 

[2019JLUS]

you end up using more fuel in stop and go traffic because you STOP AND GO over and over and over again. the engine isn't off for 5 minutes, it's off for 5 seconds before you have to creep forward with traffic again

 

[2nd 392]

With using it. My study has not yet concluded on the lifespan of the starter without using ASS.

Awww screw the quart of gas, start the without study. Starters aren’t cheap, and a PITA to change

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