Switching off engine when stopped

antodeco

Hi All,
With the advertising of mini's stop/start system, I was wondering if anybody here switches their engine off whilst stopped in traffic?

IF anyone can point out the pro's/con's of this I would be very greatful too.

Thanks

dr.bollocko

I dont. Though I am only new to Galway traffic. I might as well start.
Though in fairness, for the amount of traffic on that feckin headford road in the morning, I might as well stop the car, get out, put on a high vis jacket and start collecting money for the poor.

biko

Not at a red light but any time I'll be standing in the same spot for more than 2 mins I turn car off.
Have a notion it saves fuel, and the environment, and my lungs. Lough Atalia Road can be a pain.

Rowley Birkin QC

I don't either. Completely baseless but I get the impression that turning an engine on and off repeatedly in traffic in a car that hasn't been designed in that way would actually increase consumption. However if I know I'm going to be sitting in the same spot for maybe 10+ minutes, crash or some other incident I probably would switch off.

As I said that's completely based on my own musings so I'm wide open to correction.

craichoe

Its better to leave it running, stopping and starting causes the most wear and tear. Taxis usually leave their engines running in the rank and garda cars have a switch that leaves the engine running but you can remove the key and the car cannot be driven away.

antodeco

Hmm, I wonder what way mini have theirs designed then. I was always under the impression that turning on an engine, uses quite alot of fuel, so would be anti-fuel saving.

fletch

On routes that I know traffic lights can be red for 2+mins, I'll turn mine off. Or at train tracks.

hugoline

While learning how to drive in Switzerland, everybody is taught that if your are the 3rd car in front of a red light, turn off the engine (but again, Switzerland has an orange light coming on before the green, to give you 2 seconds to start the engine)

antodeco wrote: »

I was always under the impression that turning on an engine, uses quite a lot of fuel, so would be anti-fuel saving.

There is plenty of information on the web that suggests otherwise.
I do remember a test done by the ADAC (German car organisation) which showed that turning on an engine used about the same amount of petrol as running it for about 15 seconds. They used an external fuel tank on a highly accurate scale. At the time they recommended the 30 second rule mentioned earlier as well.
The wear and tear on the engine (mainly starter) is probably neglectable as well, as there is no higher demand for starter motors in Switzerland.

sesswhat

craichoe wrote: »

Its better to leave it running, stopping and starting causes the most wear and tear. Taxis usually leave their engines running in the rank and garda cars have a switch that leaves the engine running but you can remove the key and the car cannot be driven away.

Garda may need to have lights on etc. and so have a reason to have the engine running. Most people, including some taxi drivers, just wouldn't be bothered switching on and off.

As far as fuel consumption goes, an engine starting from cold will use more fuel for the first few minutes but this won't apply to restarting a warm engine. Arguably there will be a little wear and tear to the starter motor but I don't know how this would balance out against fuel savings.

I imagine you would not have to be sitting very long to make it worthwhile turning off but I don't know exactly how long this would be, maybe as little as 20 to 30 seconds rather than minutes.

Steve

I would switch off if I knew I would be stopped for a few minutes, e.g. level crossing.
I wouldn't do it in traffic though. Starting every few minutes will not do the battery any good as most car batterys are not deep cycle rated.
I would guess that after a start, the battery would take at least 10 minutes to recover to full charge.
The other thing to note is as it re-charges, there is an extra load on the alternator to re-charge it and this uses more fuel (similar to having A/C switched on).

biko

In Sweden it's illegal to run your engine for more than one minute if you're not in motion. This applies to railway crossings, parked waiting for someone and anywhere close to houses but not red lights.

Marcus.Aurelius

Stop start driving in the Mondeo is very bad for mpg, but turning on and off the engine periodically is even worse. I was trying it out last summer, and saw mpgs go from 25/26 to 19/20.

Seems better to leave the engine running when you're stuck motionless.

AntiVirus

Can you imagine the chaos if everyone did this when stopped at a set of traffic lights.

S.I.R

antodeco wrote: »

Hi All,
With the advertising of mini's stop/start system, I was wondering if anybody here switches their engine off whilst stopped in traffic?

IF anyone can point out the pro's/con's of this I would be very greatful too.

Thanks

you can but with turbo engined cars with turbo timers and all that crap, i dont think you need to.... the only people who get stuck in traffic are the people who dont know the streets imho.... sure if your going to be stuck for 2 or more minutes knock it off , if not just let it idle and burn the 20 cents worth of fuel :rolleyes:

zilog_jones

If I'm at lights and I know I'm going to be there longer than a minute or so I'll turn off the engine. I've been doing this nearly 2 years and haven't noticed any degredation of the battery (3/4 years old) or starter motor (10 years old assuming it's the original). The manual for my car (Ford Fiesta) actually recommends doing this - it also says that idling for 3 minutes uses the same amount of fuel as driving for 0.5km, or something along those lines.

peasant

S.I.R wrote: »

.... the only people who get stuck in traffic are the people who dont know the streets imho.... :

No offence S.I.R ...but WTF?

Ever heard of rush hour?

Balfa

biko wrote: »

In Sweden it's illegal to run your engine for more than one minute if you're not in motion. This applies to railway crossings, parked waiting for someone and anywhere close to houses but not red lights.

Are you sure that's the case? Just think of the practicalities... I'd imagine if you're stuck somewhere in a swedish winter, running the heater without the engine on, you'd drain the battery and then freeze to death before too long.

Certainly wouldn't work in hot climates like Texas, where the engine needs to be running for the A/C compressor to work. I try to turn my engine off where possible, but in the middle of July or August, I'd die in a car without A/C, even with all the windows and doors open.

zilog_jones

Balfa wrote: »

Just think of the practicalities... I'd imagine if you're stuck somewhere in a swedish winter, running the heater without the engine on, you'd drain the battery and then freeze to death before too long.

The heat in your a car comes from a small radiator connected to the engine coolant system. There's no electric element or anything. If you turn off your engine it will cool down in a few minutes. The fans won't drain the battery very quickly.

Steve

zilog_jones wrote: »

The heat in your a car comes from a small radiator connected to the engine coolant system. There's no electric element or anything. If you turn off your engine it will cool down in a few minutes. The fans won't drain the battery very quickly.

If you turn the engine off, you only get about 20 seconds of heat before the exchanger cools down though, it needs hot water from the engine circulating through it to work.

zilog_jones

Oh yeah, that makes more sense

miju

I get stuck on the Rathoath Road manned level crossing. Always turn off my engine as the fellas manning are so stupid you can be waiting there for the guts of 25 minutes at a time just for 2 trains.

Nonoperational

I'd be afraid to stop start too much! Apparently wears the timing belt more too... every 36K is plenty often enough!

whatthe...

biko wrote: »

In Sweden it's illegal to run your engine for more than one minute if you're not in motion. This applies to railway crossings, parked waiting for someone and anywhere close to houses but not red lights.

Illegal perhaps but a little ridiculous to say the least. Id say this would be very hard to police here. Cant imagine the guards wasting their time pulling up beside cars with little ear pieces hanging out the window trying to hear the noise from a hybrid engine and then jumping balls out to give you an €80 fine.

When you have the likes of unlicensed, untaxed, uninsured, drunk drivers etc on our roads, I think a law which penalises the average Joe for sitting more than a few seconds in a space outside a newsagents with the engine running whilst the missus pops in for a litre of milk or whatever is laughable.

2 Espressi

I tried this in my last car, till a relay failed and I couldn't start it...
If your car has not been designed with a start-stop system, you are only putting extra wear on the cars ignition and electrical sytem by switching it on and off yourself. Also, what happens if your car is stopped in traffic with the ignition off, and an ambulance comes up behind you, blue and twos going, and you can't get out of the way?

Esel

S.I.R wrote: »

.... the only people who get stuck in traffic are the people who dont know the streets imho....

Keeping up your usual standard of posts?