RE: What is a start-stop system? PH Explains

RE: What is a start-stop system? PH Explains

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Discussion

freecar

4,249 posts

186 months

Tuesday 23rd October 2018
quotequote all
Evilex said:
techguyone said:
buggalugs said:
In before some codger goes on about starter motors and batteries as if there the first person ever to think of that...
haha yes, every time SS is mentioned that's the first thing 'I'm not doing that, it'll wreck my... battery/alternator/starter motor....'
Wait until your battery is wrecked. The replacement cost for the appropriate stop/start battery is.....

Eye-watering.
This, I have a five year old car and the battery is starting to show signs of failure, not the biggest problem in the world but a replacement is about £160 and it needs to be coded to the car! Was all that necessary to save a thimble full of fuel?


techguyone

3,137 posts

141 months

Tuesday 23rd October 2018
quotequote all
steveb8189 said:
Lancashire Lad said:
I simply can't be doing with it. I've an SL63 which has it fitted. It means theres no such thing as a "Smart" getaway. The car has to think about starting then it decides to go. Its so frustrating.
I presume yours is an auto otherwise it would start upon clutch depression. I just sit there with my foot on the brake and then when I see the traffic starting to move in front or the traffic lights start to change I just blip the throttle to get the engine going. I do wish clicking one of the gear shift paddles would have the same effect though
Mines on a manual Ford Kuga and it's pretty much instant, I can *just* about beat it if I'm really trying but it's far from slow, dunno about autos, I suppose this is why so many sit with their brakes on at junctions etc when normal people put on the handbrake.

RobM77

35,349 posts

233 months

Tuesday 23rd October 2018
quotequote all
Evilex said:
techguyone said:
buggalugs said:
In before some codger goes on about starter motors and batteries as if there the first person ever to think of that...
haha yes, every time SS is mentioned that's the first thing 'I'm not doing that, it'll wreck my... battery/alternator/starter motor....'
Wait until your battery is wrecked. The replacement cost for the appropriate stop/start battery is.....

Eye-watering.
I'd have thought most systems will just do what my E90 320d did: decide that the battery isn't up to stop/start anymore and disable the feature. Several years later the car's running like normal, just without stop/start. If I want to get it back I just buy another battery. Sure, they're expensive, but I expect my car will last forever on its original battery, just without stop/start.

AndySheff

6,630 posts

206 months

Tuesday 23rd October 2018
quotequote all
RobM77 said:
I'd have thought most systems will just do what my E90 320d did: decide that the battery isn't up to stop/start anymore and disable the feature. Several years later the car's running like normal, just without stop/start. If I want to get it back I just buy another battery. Sure, they're expensive, but I expect my car will last forever on its original battery, just without stop/start.
In my experience the battery seems to have a life expectancy of about 10 years.

buggalugs

9,243 posts

236 months

Tuesday 23rd October 2018
quotequote all
S/S cars tend to have massive AGM batteries which to be fair do cost a few quid. But manufacturers just don’t fit small cheap batteries any more even to non SS cars.

RobM77

35,349 posts

233 months

Tuesday 23rd October 2018
quotequote all
AndySheff said:
RobM77 said:
I'd have thought most systems will just do what my E90 320d did: decide that the battery isn't up to stop/start anymore and disable the feature. Several years later the car's running like normal, just without stop/start. If I want to get it back I just buy another battery. Sure, they're expensive, but I expect my car will last forever on its original battery, just without stop/start.
In my experience the battery seems to have a life expectancy of about 10 years.
Mine's a 2010 car and start/stopped ceased to work for the previous owner latterly in their six year ownership. Strangely, when I bought the car in 2016 it never complained that start/stop wasn't working, it just didn't do it. However, in the last year it's now started saying it's broken every time I stop with a warm engine (i.e. when it would normally do a stop/start). A friend knows quite a bit about BMW electronics and says that this message is almost certainly the battery being not up to the job. No signs of it starting to fail altogether though, if that's what you meant? Or will it suddenly go? eek

millen

688 posts

85 months

Tuesday 23rd October 2018
quotequote all
I haven't driven one yet but agree the plus points may well be overstated by the manufacturers. Surely must make for a 5-10 fold increase in battery start cycles, though hot starts are obviously less demanding. And at a typical urban traffic lights, with 'real world' drivers, I'd imagine the throughput of a stream of pure S/S cars may be one, even two, down on a stream of conventional cars before the lights go read again. Presumably someone has done the experiment?

That said, as one who currently does more miles by bike than car, what gets my goat is the number of drivers who idle away at level crossings while 3 or more trains pass before the barriers open during rush hours.

rtz62

3,340 posts

154 months

Tuesday 23rd October 2018
quotequote all
I’m actually surprised that the powers that be haven’t legislated that if cars are subject of a VOSA roadside test and have the S/S system disabled that the driver would be subject of a fine.

As for this bks about ‘I find it dangerous at junctions / entering roundabouts because of the pause between putting my foot on the gas and then actually starting/moving’, have IQs dropped massively?
In my car I can
a. Stick it in sport mode, which ensures the car steps off a lot smarter than in normal mode
b. Switch off the S/S system when you get to the entrance to the roundabout (simple push of one button...) I’m sure many or most other cars so equipped have this facility too.

Hardly difficult, and all this about ‘ooh, I hardly notice any difference when s/s is engaged’, pray tell, how does one quantify that? I’ve got years of experience behind the wheel, including many driving white cars that look like battenburgs on the sides and have strange lights on top) and have never managed to gain spider-senses that allow me to decide on how many hydrocarbons, particulates etc are or aren’t being emitted into our atmosphere.

HuggyBearFezzy

63 posts

181 months

Tuesday 23rd October 2018
quotequote all
Does the constant start/stop feature not affect the components within the engine? I'm thinking things like the turbo.

I have it on my car (yes it's a turbo diesel) and like most people I switch it off as if annoys me unless I'm stuck in a long traffic jam and I know i will be stationary.

Mr Tidy

22,065 posts

126 months

Wednesday 24th October 2018
quotequote all
AndySheff said:
RobM77 said:
I'd have thought most systems will just do what my E90 320d did: decide that the battery isn't up to stop/start anymore and disable the feature. Several years later the car's running like normal, just without stop/start. If I want to get it back I just buy another battery. Sure, they're expensive, but I expect my car will last forever on its original battery, just without stop/start.
In my experience the battery seems to have a life expectancy of about 10 years.
Well I'm not a fan. I had a BMW 320td for 3 years, with CO2 emissions of 153g per km, so in December 2007 RFL was £140 p.a.

Then in January 2008 I traded it for a pre-registered 123d registered in September 2007 which had stop/start so CO2 was 138g per km and RFL was £115 in January 2008.

So a "massive" saving of £25 a year!

In March 2012 just before 55K miles the 123d needed a new AGM battery that needed coding, so even at an Indy a replacement cost over £250.

Then in February 2014 just before 77K miles it needed a new starter motor, which cost a mere £600+. I turned the stop/start off every time I used it after that! banghead

So saving a couple of hundred in RFL cost me nearly a thousand in repairs over 6 years - great! banghead

I sold my 123d before the N47 cam-chain wrecked the engine (that was before the "Quality Enhancement" programme) and got a Z4 Coupe. It had it's first new battery at 10 years old and it cost just £90 + VAT fitted!

So in simple terms I'd rate stop/start as a gimmick, but in real terms I'd rate it as cr*p! banghead




underphil

1,245 posts

209 months

Wednesday 24th October 2018
quotequote all
Mr Tidy said:
Well I'm not a fan. I had a BMW 320td for 3 years, with CO2 emissions of 153g per km, so in December 2007 RFL was £140 p.a.

Then in January 2008 I traded it for a pre-registered 123d registered in September 2007 which had stop/start so CO2 was 138g per km and RFL was £115 in January 2008.

So a "massive" saving of £25 a year!

In March 2012 just before 55K miles the 123d needed a new AGM battery that needed coding, so even at an Indy a replacement cost over £250.

Then in February 2014 just before 77K miles it needed a new starter motor, which cost a mere £600+. I turned the stop/start off every time I used it after that! banghead

So saving a couple of hundred in RFL cost me nearly a thousand in repairs over 6 years - great! banghead

I sold my 123d before the N47 cam-chain wrecked the engine (that was before the "Quality Enhancement" programme) and got a Z4 Coupe. It had it's first new battery at 10 years old and it cost just £90 + VAT fitted!

So in simple terms I'd rate stop/start as a gimmick, but in real terms I'd rate it as cr*p! banghead


Isn't that more a problem with BMW's engineering?

As posted earlier, manufacturers like Mazda have a system where no additional components are needed and the battery isn't used to re-start the engine

janekgti

1 posts

192 months

Wednesday 24th October 2018
quotequote all
This is very clever function start and stop haha ask yourself why people use turbo timers? To cool turbo before switching off hot engine in new cars this rule do not exist start stop do this for you any time you stop 😂 happy days than after little while turbo will be gone same as egr and egr cooler nice fat bill to pay.
My own expirience working for JLR last 5 years.

Shiv_P

2,727 posts

104 months

Wednesday 24th October 2018
quotequote all
janekgti said:
This is very clever function start and stop haha ask yourself why people use turbo timers? To cool turbo before switching off hot engine in new cars this rule do not exist start stop do this for you any time you stop ?? happy days than after little while turbo will be gone same as egr and egr cooler nice fat bill to pay.
My own expirience working for JLR last 5 years.
10.5 years and your first post!! Top lurking!

HRCM

70 posts

88 months

Wednesday 24th October 2018
quotequote all
Baldchap said:
I have recoded my car to permanently disable Start/Stop as well as disable pretend exhaust noises. I'll buy a diesel if I want to save fuel.
This

The Mad Monk

10,474 posts

116 months

Wednesday 24th October 2018
quotequote all
Lancashire Lad said:
I simply can't be doing with it. I've an SL63 which has it fitted. It means theres no such thing as a "Smart" getaway. The car has to think about starting then it decides to go. Its so frustrating.
Why did you buy a car that had it fitted?


Edited by The Mad Monk on Wednesday 24th October 21:02

legless

1,688 posts

139 months

Wednesday 24th October 2018
quotequote all
janekgti said:
This is very clever function start and stop haha ask yourself why people use turbo timers? To cool turbo before switching off hot engine in new cars this rule do not exist start stop do this for you any time you stop ?? happy days than after little while turbo will be gone same as egr and egr cooler nice fat bill to pay.
My own expirience working for JLR last 5 years.
Cars that use turbo timers also have oil-cooled turbochargers.

Every turbocharged s/s car I've ever seen uses a water-cooled turbocharger, with an auxiliary electric pump to circulate the coolant even when the engine's not running.


manracer

1,544 posts

96 months

Wednesday 24th October 2018
quotequote all
I thought we were always told that stopping the engine when stationary and restarting it used not fuel?

I find with VW's implementation that you can't use auto hold and stop start concurrently?

techguyone

3,137 posts

141 months

Wednesday 24th October 2018
quotequote all
legless said:
janekgti said:
This is very clever function start and stop haha ask yourself why people use turbo timers? To cool turbo before switching off hot engine in new cars this rule do not exist start stop do this for you any time you stop ?? happy days than after little while turbo will be gone same as egr and egr cooler nice fat bill to pay.
My own expirience working for JLR last 5 years.
Cars that use turbo timers also have oil-cooled turbochargers.

Every turbocharged s/s car I've ever seen uses a water-cooled turbocharger, with an auxiliary electric pump to circulate the coolant even when the engine's not running.
I thought Turbo timers died a death in the 90's to be honest.

steveb8189

473 posts

190 months

Thursday 25th October 2018
quotequote all
techguyone said:
Mines on a manual Ford Kuga and it's pretty much instant, I can *just* about beat it if I'm really trying but it's far from slow, dunno about autos, I suppose this is why so many sit with their brakes on at junctions etc when normal people put on the handbrake.
Certainly in my Octavia DSG you have to keep your foot on the brake to stop it crawling and the handbrake won't /shouldn't hold it when it;'s in drive. You can put it in neutral and the engine stays stopped but as soon as you lift your foot off the brake it starts again. Had many a fun traffic jam working out what actually kicks it in...

untakenname

4,953 posts

191 months

Thursday 25th October 2018
quotequote all
The extra time needed when you have a queue of 15 start stop cars at the lights and each one needs to engage before moving soon adds up.
imo start stop only makes sense for hybrids as the car can use electricity to creep forward in traffic jams.
No matter how much more heavy duty they make the components constantly starting and stopping the engine will put more wear on it compared to simply idling.