Vehicles with Start/Stop technology?

peking97

Would appreciate opinions on vehicles with Start/Stop technology, Bluemotion and the like. Surely this must be very hard on the starter motor or am I missing something obvious? Can the feature be disabled if required?

kirving

I'm not 100% certain on all the methods different manufacturers come up with, but one type of system reads the position of the pistons, and stops the engine so that one cylinder is pressurized. When you go so start off again, diesel is injected (or petrol is injected, and the spark plug fires) and the engine will start again.

Edit: That's Mazda's SISS, Some others just use the starter motor, which is less complicated, but slower.

Eric Cartman

id say starter motors and batteries get a fierce hard time in those

DublinDilbert

Do some not use the alternator as a motor to start the engine? I think some also mess with the compression by modifying the inlet cam to make it easier to start.

Either way, they aren't just using a standard starter motor / battery combination.

mickdw

The only stop start ive had experience with is the lexus gs450h. This hybrid system is seemless in that you cannot really hear or feel the engine coming in as it runs at slow speed on the electric motors. I feel stop start should be left to the petrol hybrids. I would love to know how smooth the switch on is in a diesel passat. I cannot see it being so smooth and yes I imagine it is severe on the motor that starts it.

DublinDilbert

DublinDilbert wrote: »

Do some not use the alternator as a motor to start the engine?

Dunno, can't fathom how that would work to be honest, must go googling :pac: (din dins not for a couple of hours yet)

DublinDilbert

RoverJames wrote: »

Dunno, can't fathom how that would work to be honest, must go googling :pac: (din dins not for a couple of hours yet)

The alternator would actually make quite a powerful brushless dc motor. It would need power electronics to create a rotating magnetic field, but that's not too hard to do...

Jimmy Garlic

Too much crap to potentially go wrong . Avoid.

Topdeck

Jimmy Garlic wrote: »

Too much crap to potentially go wrong . Avoid.

agreed

Ali Babba

Fiat tried this on the Ritmo of all cars, in the mid 80's and it wasn't a success then either, like some other posters mentioned it has to be hard on the starter/battery etc. It's just a gimmick really just like all the other global warming/climate change crap.

colm_mcm

had this on a company car and it was grand. uses an integrated starter and alternator.
Honda use a version of this on the Civic IMA I believe, not exactly rocket science, so hardly a potential minefield reliability wise.

Marcusm

Jimmy Garlic wrote: »

Too much crap to potentially go wrong . Avoid.

Too simplistic an approach, IMO. I have had a stop/start Mini Cooper S for 3 years and the stop/start works fine when you get used to it. Initially had problems with cutting out because I was not gunning it enough. Most of my driving is urban London but even more valuable around Dublin where there's even less free flowing traffic. Generally these cars have specialised starters and battery packages, and covered by warranties.

Have noticed a significant difference on fuel consumption.

colm_mcm

must agree, while it sounds a bit like a dodge to get a car into a lower emissions bracket (it well may be!) when I had a car equipped with it - the time the engine was turned off in traffic accounted for a few hours a month (there's a timer on the trip computer to tell you)

Max_Damage

Jimmy Garlic wrote: »

Too much crap to potentially go wrong . Avoid.

Couldn't have said it better myself.

Owen

Marcusm wrote: »

Too simplistic an approach, IMO. I have had a stop/start Mini Cooper S for 3 years and the stop/start works fine .... Have noticed a significant difference on fuel consumption.

I can tell you now, that has bugger all to do with the stop/start system. I think stop start contributes (From the dozens of powerpoint presentations I'd to sit through on Efficient Dynamics) only something like .7% to fuel efficiency.

It's a red herring designed to make you feel great, the real savings come from clever injection technology, 6 speed gearboxes, low rolling resistance tyres, lightweight cars, etc, etc, etc.

dingding

My wife has it on a BMW 118D

You can disable it by pressing a button on the dash.

Does not really work on short journeys as the engine has to heat up first.

-Chris-

You can disable in VAG too. It's a gimmick imho.

Jimmy Garlic

I think Renault are making it standard in all models from next year on. As if they don't have enough problems already.

crosstownk

DublinDilbert wrote: »

Do some not use the alternator as a motor to start the engine?

Yes. The PSA stop/start diesels use a 'reversible alternator'. It claims to reduce wear on the starter and is faster at restarting the the standard starter system.

It is quick at the restart. I've driven both the PSA and BMW stop/starts and the PSA is much faster (400ms) and quieter (the PSA is silent) at the restarting. Also there is no 'shudder' that a starter motor gives.

I can't comment on the reliability of the PSA as it hasn't been around long enough.

opinion guy

PaintDoctor wrote: »

I can tell you now, that has bugger all to do with the stop/start system. I think stop start contributes (From the dozens of powerpoint presentations I'd to sit through on Efficient Dynamics) only something like .7% to fuel efficiency.

It's a red herring designed to make you feel great, the real savings come from clever injection technology, 6 speed gearboxes, low rolling resistance tyres, lightweight cars, etc, etc, etc.

No the real saving comes from being in a lower tax bracket!! Mainly a saving for the car company granted since they don't reduce the prices generally.

pajo1981

I have it on my own yoke (BMW), and it works fine.

As for the la las giving out about reliability, I'm sure that the stop-start system was considered when the starter motor was being specified.

pajo1981

Jimmy Garlic wrote: »

I think Renault are making it standard in all models from next year on. As if they don't have enough problems already.

??

Joe 90

PaintDoctor wrote: »

I can tell you now, that has bugger all to do with the stop/start system. I think stop start contributes (From the dozens of powerpoint presentations I'd to sit through on Efficient Dynamics) only something like .7% to fuel efficiency.

It's a red herring designed to make you feel great, the real savings come from clever injection technology, 6 speed gearboxes, low rolling resistance tyres, lightweight cars, etc, etc, etc.

What lightweight cars?

opinion guy

pajo1981 wrote: »

I have it on my own yoke (BMW), and it works fine.

As for the la las giving out about reliability, I'm sure that the stop-start system was considered when the starter motor was being specified.

My VAG had stop start and I have to say I love it. Apparently when they develped it they did loads of research into beefing up the starter motor etc. Anyhow - it always starts first time. Its very inobtrusive and the car is just so wonderfully quiet when sitting at traffic lights. Oh and my 170bhp yoke is only 152euro to tax a year:D

Owen

Joe 90 wrote: »

What lightweight cars?

Should have said lighter - for example, when BMW started championing Efficient Dynamics, things like rear trailing arms were redesigned for the later models to be spun from Aluminium, saving nearly 5 Kgs a side on the car. There were plenty of other similar savings made with body panels, engine components, etc.

opinion guy wrote:

the real saving comes from being in a lower tax bracket!

That too shall pass. The Government won't keep cheap tax out there forever.

Marcusm

PaintDoctor wrote: »

I can tell you now, that has bugger all to do with the stop/start system. I think stop start contributes (From the dozens of powerpoint presentations I'd to sit through on Efficient Dynamics) only something like .7% to fuel efficiency.

It's a red herring designed to make you feel great, the real savings come from clever injection technology, 6 speed gearboxes, low rolling resistance tyres, lightweight cars, etc, etc, etc.

It's true that cars with s/s generally have other fuel saving features but I mean a direct comparison. for the first couple of months, I religiously disabled the stop/start features. I noticed the improved fuel consumption when I started using it. I didn't change my usual drives, driving habits nor have I lost any weight!

Owen

You may have noticed an improvement, but it's not down to the stop start system. I know MINIs backwards, and had nice long chats with the engine designers at product launches. The fuel you save by turning the engine off is usually wasted while starting it back up again. It only gives a benefit for long stops - and that's in the rare instances when the car doesn't prematurely turn itself back on again because it needs the power from the engine to run electrical/cooling devices.

Idleater

I believe StopStart helps manufacturers get to Euro5 emissions targets that come into effect on Jan 1 2011.

Being honest (and I have the S/S on the MiTo) I don't notice it one way or another how it affects/doesn't affect fuel consumption, but I have gotten used to it in traffic when it goes quiet. There are times when traffic is bad that you are sitting in the one spot for 5 minutes so it can't hurt fuel consumption, but then again, that sort of driving (urban) is shocking for fuel consumption anyway so like tescos, every little helps.

One side effect that I do like is that the engine restarts when I put the clutch in, this is handy if you have stalled, which by the by I have noticed I do more now. So either I'm getting lazy (quite likely) or the turbo (or something else) in the engine/drive train makes it easier to cut out than what I was used to in the old car.

opinion guy

Idleater wrote: »

I
One side effect that I do like is that the engine restarts when I put the clutch in, this is handy if you have stalled, which by the by I have noticed I do more now. So either I'm getting lazy (quite likely) or the turbo (or something else) in the engine/drive train makes it easier to cut out than what I was used to in the old car.

Actually I have noticed this exact same thing!!