General Usefulness Of Start/Stop

[GettinBetter]

PROS:
1. Checks the status of the battery and earth system.
2. Checks the status of the microswitches that determine whether it should work or not.

CONS:
1. Stops engine for periods too short for good fuel efficiency/wear & tear.
2. Stops engine even after a spritely burst of the turbo.

 

[FiatMatt94]

Call me old fashioned but I hate start stop systems & won't buy a car which has it, it also wears batteries & starter motors out quicker.

 

[Piccolo Nero e Bella]

Usefulness? Negligible at best. Just allows FIAT to make dubious claims about fuel consumption, efficiency and emissions.

 

[GettinBetter]

Usefulness? Negligible at best. Just allows FIAT to make dubious claims about fuel consumption, efficiency and emissions.

Yes, same as the hybrid,

 

[Tropicalmike]

FYI The 1.0 mild hybrid engine uses the alternator to start the engine during stop/start operation. Also adding in a bit of power from the hybrid battery when accelerating. Starter motor for initial engine start only.

 

[RalphM]

Can't be good especially for the turbo if it has one and the starter.

 

[Tropicalmike]

Can't be good especially for the turbo if it has one and the starter.

I think the 1.0 hybrid is 3 cylinder naturally aspirated engine. I drove one as a rental and the regenerative charging when you take your foot off the gas takes a bit of getting used to compared to a conventional engine.

 

[steveras57]

FYI The 1.0 mild hybrid engine uses the alternator to start the engine during stop/start operation. Also adding in a bit of power from the hybrid battery when accelerating. Starter motor for initial engine start only.

We should all be grateful fiat didnt manage to turn it in to a stop/stop system despite there best efforts .

 

[blue monkey]

Mine is permanently switch off. It's just annoying and serves no purpose.

 

[steveras57]

Mine is permanently switch off. It's just annoying and serves no purpose.

thats what most folk do i just cant stand the orange light telling me its of glaring at me all the time!

 

[Piccolo Nero e Bella]

thats what most folk do i just cant stand the orange light telling me its of glaring at me all the time!

 

[Ralf S.]

The Younger Mrs S' Rasputin has a non-S/S battery which has *just* insufficient charge that the S/S never cuts the engine, but does start it when I stall it.

Every summer, or after veeery long runs, the battery does have enough juice for the car to stop the engine.. but usually it's only for just a few seconds before the car changes its mind again, which does get annoying.

On the other hand, one long hot summer the battery obviously hit a purple patch and the S/S started working perfectly.. that is, it turned off and never restarted the engine until I pressed the clutch in. I was impressed.


Ralf S.

 

[ZaphodB]

I bought and fitted a little pcb on my last start/stop as soon I bought the car (new)

Left disabled for the next ten years , it just wears out stuff.

Prior to fitting the PCB it's annoying that it opts you in every day.... the pcb just waited a second on power up and then emulated you pressing the button (to turn off)

I was so glad this 595 doesn't have it.

 

[sandeel999]

They are the biggest cause of traffic hold ups. I love the way I'm half way to the next lights by the time the stop/start next to me has even moved, but hate when I'm behind one and you wait and wait and then finally they pull off. I doubt it has any fuel saving credentials at all.
Then there's lane assist another pointless addition to a car on a normal road, my daughter hired a almost new golf the other week. Didn't know it had lane assist.
Whilst trying to overtake a cyclist it nearly diverted here into it, frightened the life out of her. I had to work out how to turn it off so she could do it before every trip, pointless.

 

[Piccolo Nero e Bella]

The Younger Mrs S' Rasputin has a non-S/S battery which has *just* insufficient charge that the S/S never cuts the engine, but does start it when I stall it.

Every summer, or after veeery long runs, the battery does have enough juice for the car to stop the engine.. but usually it's only for just a few seconds before the car changes its mind again, which does get annoying.

On the other hand, one long hot summer the battery obviously hit a purple patch and the S/S started working perfectly.. that is, it turned off and never restarted the engine until I pressed the clutch in. I was impressed.


Ralf S.

Mine ran for three years (2014-2017) with a non-SS battery and the SS performed to spec. Then I got the EFB which is still in the car now but at the same time turned SS off. Fortunately my car has the more sensible arrangement in that when you switch off SS it stays off.

 

[Tropicalmike]

On a 500 manual . From my experiences to get it working. For those who hate the start stop and don't want the orange light on the cluster. Disconnect the mechanical link on the neutral sensor under the gear lever . Such that the ECU never thinks it is in neutral. That was the fault on my car and no fault shows on dash or in MES DTC.

 

[rmjbn1]

I always wonder what the break-even point is for there to be a net gain in fuel consumption and emissions?

As in, how long does an engine need to be off, to counter the extra fuel used on start-up and to recharge the battery?

I've heard 20 seconds mentioned, but never seen any sources or studies to support this.

(Plus then the extra emissions to manufacture & dispose of all them consumable DMFs and beefier batteries etc...)

 

[Didge3]

Never particularly understood the hate for S/S, every car I've had it on its been quite a nice feature. Bit of silence at traffic lights is nice and seems pointless to be burning fuel when stopped for a sufficient amount of time. Fiats implementation of it is a bit crap, I like that you have to be in neutral with the handbrake on for it to cut in as opposed to VAG solutions where anytime the clutch is dipped and you're at a stop it cuts in. The Fiat system gives more control over when you want to use it and when you don't (e.g. waiting to pull out of a busy junction I want the engine running so there isn't a delay)
However in my limited experience it doesn't work all that reliably on Fiats, never could get it reliably going on my Punto TwinAir even with a brand new AGM battery.
On the other hand my sisters Ford Fiesta racked up 120k on its original starter motor and battery in 11 years with S/S being used regularly, it was reliable, the turbo didn't fail despite popular belief.
Personally just don't understand the hatrid of it.

 

[Greasytrucker]

My Mini Cooper diesel has it but it’s never worked as the battery wasn’t too clever when I bought it, I fitted a nearly new one but never bothered programming it in so it still thinks it’s knackered so the S/S never bothers me

 

[StevenRB45]

Never particularly understood the hate for S/S, every car I've had it on its been quite a nice feature. Bit of silence at traffic lights is nice and seems pointless to be burning fuel when stopped for a sufficient amount of time. Fiats implementation of it is a bit crap, I like that you have to be in neutral with the handbrake on for it to cut in as opposed to VAG solutions where anytime the clutch is dipped and you're at a stop it cuts in. The Fiat system gives more control over when you want to use it and when you don't (e.g. waiting to pull out of a busy junction I want the engine running so there isn't a delay)
However in my limited experience it doesn't work all that reliably on Fiats, never could get it reliably going on my Punto TwinAir even with a brand new AGM battery.
On the other hand my sisters Ford Fiesta racked up 120k on its original starter motor and battery in 11 years with S/S being used regularly, it was reliable, the turbo didn't fail despite popular belief.
Personally just don't understand the hatrid of it.

I've never had one where it didn't idle forever with the clutch down. The VW dsg ones seem mildly hilarious I do cringe somewhat when you hear them stop the car for a quarter of a second because you've come to halt behind someone turning right. In theory they designed for it but in practice that feels plain abusive.

Handbrake on is new on me as long as clutch is up both Toyota and Citroën stop even if you're on the footbrake. To be fair that is terrible practice but they do.

I think as with most things there are good and bad implementations, the Toyota one as you'd expect is absolutely spot on given their history in hybrid cars. Engine stop and start is instant and without any noise or vibration or flare in revs it's just suddenly at idle rpm before you've pressed the clutch to the floor. Citroën less so, the dmf (Toyota has a solid flywheel as it's a 4 pot) and the general feel is a bit agricultural and vibratey you can also hear the starter and there's times it's re-engaged the starter before fully disengaging it which sounds as awful as you'd expect.

Both do the job though...and also both have an electric coolant pump as well as standard water pump so cooking the turbo while stationary is not really a thing. Most things have them so your heater doesn't stop working as otherwise the coolant in the heat exchanger could lose all heat if you stopped for a few minutes.

Also both work after 8 years on the original battery...I say this the Citroën one currently doesn't but it's done 200 miles across about 5 days since march so the battery is crying somewhat once it's back in regular use I expect it to live again.

Re. Another line of conversation apparently the break even point is about 7 seconds re. Switching off or leaving it running. Given I've had both cars on S/S at various times for up to 5 minutes they must be saving something. Think it was engineering explained that came up with this figure by comparing idle fuel use to fuel needed to start an engine.

This is probably less on something like the Toyota where it only stops the piston in the correct place to restart and uses a reduced fuel pulse on initial fire for S/S.