All - I've started so I'll stop

Honest John Back Room » Motoring discussion
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Mon 19 Mar 2012 09:36
All - I've started so I'll stop - large portion
I am seeing a few threads lately on the subject of the new eco idle-stop systems on engines. It got me wondering, and I am watching this space on these new "I've-started-so-I'll-stop" systems.

My prediction is faults and defects will pop up. Mind you one doesn't have to be Nostradamus to see it coming - anything new has teething troubles. The problem is the poor old owner gets to be the one to wear it all. I am so cynical.

The actual systems appear to fall into three basic categories (correct me if I am wrong). The basic ones seem to be just a brute force method of flinging the engine over on the existing starter system. Smarter ones stop the engine at certain positions, which leave cylinders primed to fire more easily with a bit of a fling from a combined alternator/starter. Other methods use a primed cylinder to recieve a squirt of fuel and spark and it is enough to fling the motor over and then start and continue running - I think Mazda have this system.

Or so I have read. Please feel free to add to my knowledge.

Plainly a system that does not encourage extra wear on components is the better option but of course with that comes more complexity. Groan.

And on the subject of wear and tear I for one, regardless of the method of re-start, don't like the idea of engine oil pressures dissipating every time I stop the car - no good can come from an increase in the number of cycles of building oil pressure from zero. Although I do accept the oil is hot and it is not the same as a cold start. My point still stands though.

Couple that scenario with the rise in small highly strung engines being asked to deliver the same power as previous generations and it merely adds to the stresses on the motor. There will be problems.

Anyway. I have started, so I will stop.



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Mon 19 Mar 2012 09:55
All - I've started so I'll stop - bonzo dog

Can't say I understand the technology but I guess you are saying what I presume will be the case - constant stop / starting cannot be good for the long-term well-being of the motor.

To me it is another example of the endless drive by governments forcing manufacturers to reduce emissions regardless of other costs, namely repairs to failed parts. If people don't like it they should complain to their MP not to the dealer or manufacturer

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Mon 19 Mar 2012 10:05
All - I've started so I'll stop - daveyjp

"My prediction is faults and defects will pop up"

Please let us know when we produced a car that never failed - the AA has been around for a long time and doesn't seem to be struggling for work.

The average lifespan of a car is now 8 years and cars with 7 year warranties are available, offering a chance for nervous owners to mitigate any problems.

"regardless of the method of re-start, don't like the idea of engine oil pressures dissipating every time I stop the car"

Do you know that this actually happens, or is the system designed to maintain oil pressure?

For luddites all stop/start cars have a button to turn the system off.

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Mon 19 Mar 2012 10:20
All - I've started so I'll stop - unthrottled

For luddites all stop/start cars have a button to turn the system off.

I know you are a fan of this but (apart from the road tax dodge) have you worked out what you actually save in use?

Just because someone doesn't adopt a revamped idea, doesn't make them a luddite.

Snce the oiling system is basically a series of controlled leaks, it would be quite difficult to maintain pressure while the pump isn't turning. Nevertheless, I'd be surprised if the lack of lubrication proved to be a real problem.

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Mon 19 Mar 2012 12:08
All - I've started so I'll stop - daveyjp

"Just because someone doesn't adopt a revamped idea, doesn't make them a luddite."

Expcet that's exaclty what a luddite is.

Luddite: One who opposes technical or technological change.

I'm not a fan, just someone who has experienced the system for 12 months and had no problems.

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Mon 19 Mar 2012 12:19
All - I've started so I'll stop - unthrottled

Luddite: One who opposes technical or technological change

Yes, but with negative connotations of narrow-minded and irrational fear. There is nothing irrational or superstitious about evaluating the merits of a 'new' technology and deciding that it does not offer an overall advantage over existing technologies.

There are lots of unwelcome 'improvements' on modern cars. Rear axle disc brakes, big wheels and colour coded door mirrors immediately spring to mind.

I'm not a fan, just someone who has experienced the system for 12 months and had no problems.

Adopters say the same thing about magnets on fuel lines!

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Tue 20 Mar 2012 10:45
All - I've started so I'll stop - Roly93

The average lifespan of a car is now 8 years and cars with 7 year warranties are available, offering a chance for nervous owners to mitigate any problems.

Thats a depressing and backward situation really. Before cars became packed with impossible and cost-prohibitive to fix electonics, you could make a car last many years with low mileage and good care and maintenance.

Now you have no choice, no matter how much you change the oil and polish the bodywork, when your car is 8 years old it is highly likely that you may get a fault which is more expensive than the car to fix.

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Mon 19 Mar 2012 10:30
All - I've started so I'll stop - unthrottled

Smarter ones stop the engine at certain positions, which leave cylinders primed to fire more easily with a bit of a fling from a combined alternator/starter. Other methods use a primed cylinder to recieve a squirt of fuel and spark and it is enough to fling the motor over and then start and continue running - I think Mazda have this system.

So did the Model T. If you flooded the engine as you switched it off, there would be plenty of unburned fuel sloshing around the cylinders. The engine could (hopefully) be restarted simply by moving the spark advance lever until the cylinder on the expansion stroke was fired.

Engines always stop in the same place. With a direct injection system it's somtimes possible to squirt fuel into the relevant cylinder immediately before firing it. But the 2012 engines have the same problem as the Model Ts. Stationary cylinders can hold fuel-but not compressed air.

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Mon 19 Mar 2012 14:37
All - I've started so I'll stop - large portion
I am a new to HJ's and I won't be back, as I suspect a lot of new people do - indeed there is an "ask" for new people to come back. The reason. The usual argumentative, brusque, chest-beating troll always raise their self important side and it just drives people away. I am not intimidated but rather just can't be bothered dealing with the shallower side of people.

Yes, I am talking to you daveyjp.

I was merely floating some thoughts on a fairly new topic to provoke some mature commenting and along you come and cherry pick bits of the post and urinate all over them. You are like a tom cat spraying to claim the high ground.

Goodbye HJ.
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Mon 19 Mar 2012 15:23
All - I've started so I'll stop - mrmender

^^ Well said^^

I used to be a regular here. There used to be loads of good guys on here. About 3 or 4 years ago "Something happend!"

Not the same place anymore. I look in maybe once a month. Ive not posted here for years

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Mon 19 Mar 2012 15:38
All - I've started so I'll stop - jamie745

I think i'm right in saying stop-start isn't really anything new, didnt Toyota experiment with it in the 70s and VW in the 80s?

I take the point about potential defects as well as the point that we've never made an infallible motor vehicle, but I feel this insanely obsessive focus on fuel economy and emissions, mostly driven by Government taxation and EU bigwigs has led to a reduction in vehicle reliability. 15 years ago you could buy a diesel and it'd run for miles, now it fragility caused as a biproduct of saving polar bears means its transported like Hannibal Lecter.

With that in mind its daft to put even more unneccessary things on a car. Stop Start is purely just something to go wrong.

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Mon 19 Mar 2012 17:34
All - I've started so I'll stop - concrete

I agree with Jamie, the whole business of engine efficiency is driven by taxation and will drive us into some unworkable situations. I run one of the last 1.9PD 130 Tdi diesels, and have said on this forum I will look long and hard when replacement time comes and maybe go for another Honda petrol, even though I do about 30K miles per year. I would not entertain stop/start on any vehicle I run. ( purely a personal choice before I get slated) My money, my choice. I think any potential benefits are removed by potential future maintainance costs, until proved conclusively otherwise.

I am sorry to read that large portion is disappointed with the forum. However it is just like a barroom debate, one question, ten people, ten different points of view. You just have to filter out which you agree with and which you don't. Some do regard it as a pi**ing contest but you can't expect everyone to agree with you or not exercise their right to deconstruct your arguments. Sometimes it is dismaying but it is all part of the mix. Don't be put off just come back with your replies. You wouldn't leave the pub just because someone disagreed with you so don't leave the forum.

Best to all. Concrete.

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Tue 20 Mar 2012 10:50
All - I've started so I'll stop - Roly93

I agree with Jamie, the whole business of engine efficiency is driven by taxation and will drive us into some unworkable situations. I run one of the last 1.9PD 130 Tdi diesels, and have said on this forum I will look long and hard when replacement time comes and maybe go for another Honda petrol, even though I do about 30K miles per year. I would not entertain stop/start on any vehicle I run. ( purely a personal choice before I get slated) My money, my choice. I think any potential benefits are removed by potential future maintainance costs, until proved conclusively otherwise.

I'm on my third generatiuon oif VaG diesel since this engine, and nothing touches it for efficiency as far as I can see. Brilliant motors, I drove to the Cote D'Azur in my car and it still returned 47-48 MPG even being ragged way beyond normal UK motorway speeds. Tear in corner of eye while writing this !

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Mon 19 Mar 2012 16:34
All - I've started so I'll stop - unthrottled

Ive not posted here for years

Um...?

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Mon 19 Mar 2012 19:44
All - I've started so I'll stop - wrangler_rover

Is anybody able to say how many miles wear a cold start and a hot start is equivalent to on a car engine and would the figures be different for petrol and diesel? There must be something built into the software of cars with variable servicing intervals that takes the number of starts into account.

Not such a silly question as in the past, I have had experience of jet engines and one start was considered equivalent to 10 running hours.

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Mon 19 Mar 2012 20:16
All - I've started so I'll stop - unthrottled

It's a very good question and I don't think there's a definitive answer. For instance Idling is hard on camshaft lobes. Excess petrol can dissolve oil on cylinder bores. Diesels don't have this problem. But the higher cylinder pressures impose higher loads on the rod bearings and the top compression ring etc. It's swings and roundabouts.

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