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Old 29th June 2011, 15:46   #16
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Default Re: Fuel Consumed During Start

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Is your Accent fitted with a Scangauge?

Didnt understand why are you sorry about the Accent.
Yes Accent is fiited with Scangauge. Sorry about the fact that I missed mentioning about the Car.
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Old 29th June 2011, 15:54   #17
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Default Re: Fuel Consumed During Start

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Yes Accent is fiited with Scangauge. Sorry about the fact that I missed mentioning about the Car.
Got it now, now I am sorry about the confusion

During the cold start what kind instantaneous FE numbers does the Scangauge show? How much it is different from an warmed up idle condition? Very curious to know.
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Old 29th June 2011, 16:37   #18
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Default Re: How much fuel is consumed on engine start?

The fuel consumed on start would depend on the engine capacity too, right?
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Old 29th June 2011, 17:42   #19
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Default Re: How much fuel is consumed on engine start?

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Originally Posted by dot View Post
During the cold start what kind instantaneous FE numbers does the Scangauge show? How much it is different from an warmed up idle condition? Very curious to know.
Umm.. I don't think a scanguage can show how much fuel is used just for starting. Though you can differentiate between cold idling and warmed up idling.
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Originally Posted by libranof1987 View Post
The fuel consumed on start would depend on the engine capacity too, right?
Fuel consumed on start will depend on engine capacity, but then, the total FE will also. . When we look at fuel consumed on start as a % of FE/hr, the value will remain same with higher capacity engines.

AFAIK, its the number of cylinders (not capacity exactly) that make a difference.

===============================

Coming to the topic. It was in olden carburetor days, that more fuel was required to fire an IC engine, but newer programmed efi engines are pretty frugal, and very very less fuel is required for starting an engine, as compared to olden days. Fuel required to start an engine, may be approx = 15 seconds of idling. But then, the wear and tear of the starter motor, and the current drawn from the battery, all make it worthwhile to shut off the car if idling time is more than 30 secs.

Last edited by dhanushs : 29th June 2011 at 17:44.
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Old 29th June 2011, 20:49   #20
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Default Re: How much fuel is consumed on engine start?

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Originally Posted by dhanushs View Post
Umm.. I don't think a scanguage can show how much fuel is used just for starting. Though you can differentiate between cold idling and warmed up idling.

Fuel consumed on start will depend on engine capacity, but then, the total FE will also. . When we look at fuel consumed on start as a % of FE/hr, the value will remain same with higher capacity engines.

AFAIK, its the number of cylinders (not capacity exactly) that make a difference.

===============================

Coming to the topic. It was in olden carburetor days, that more fuel was required to fire an IC engine, but newer programmed efi engines are pretty frugal, and very very less fuel is required for starting an engine, as compared to olden days. Fuel required to start an engine, may be approx = 15 seconds of idling. But then, the wear and tear of the starter motor, and the current drawn from the battery, all make it worthwhile to shut off the car if idling time is more than 30 secs.

Not to mention - on my Figo when you crank the starter, power is cut off from everything, including the Bluetooth, and then it spends time synchronizing, screwing up the music playback and (if you were on a call) the whole teleconference.
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Old 29th June 2011, 22:13   #21
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Default Re: How much fuel is consumed on engine start?

This is a different way of telling that more fuel is consumed during cold start conditions.

My apartment to office used to be a kilometer apart. So by the time I would reach office, the Ikon used to be barely warmed up. Then, for the rest of the day, the car would be sitting in the parking lot. The cycle would repeat in the evening. As a result FE would be about 11.5-12.

Then the office moved to a different building and the home to office distance increased to eight kilometers one way. With the increase in commute, the car could warm up and sprint for a decent time. FE also increased to 13 to 13.5.
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Old 29th June 2011, 23:09   #22
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Default Re: How much fuel is consumed on engine start?

It consumes a helluva lot of fuel at start-up! My MID displays as low as 3 kmpl before increasing steadily and evening off at (typically) 9-11 kmpl. In trips where I start the car and immediately am held up in crawling traffic, it never goes beyond 5 or 6 kmpl.

I have an overactive imagination and sometimes wonder if I should just push it till it starts
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Old 30th June 2011, 09:37   #23
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Default Re: How much fuel is consumed on engine start?

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I have an overactive imagination and sometimes wonder if I should just push it till it starts
Whether you push it or crank it, it will consume the same amount of fuel!
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Old 30th June 2011, 09:56   #24
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Default Re: Fuel Consumed During Start

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Originally Posted by bluevolt View Post
In general the rule is to switch off the engine if one has to wait for over 60 seconds (timers at red light are very beneficial for this purpose). I don't think that it will be sensible to switch off the engine for 20-40 seconds stop. The reason is that first it causes starter to wear unnecessarily, secondly it consumes battery power and finally starting the engine sometimes consumes more oil than idling for 20-30 seconds as many of you must have noted that when we start the car, it idles at much higher RPM and then settles. This will ultimately consume more fuel.
I agree with you, only switch off the engine at the signal if you are going to wait for atleast 60 seconds. shorter than that and the benefit of saving fuel is negated.
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Old 30th June 2011, 13:08   #25
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Default Re: How much fuel is consumed on engine start?

Does anyone have any evidence to prove a starter failed because of stopping and starting the engine repeatedly?If you assume a starter is designed for about 1,00,000 operations in its lifetime, and if I swithed my engine off and on about ten times a day, every day of the year, the starter would still serve about 27 years.
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Old 30th June 2011, 16:43   #26
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Default Re: How much fuel is consumed on engine start?

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Originally Posted by dot View Post
This is a different way of telling that more fuel is consumed during cold start conditions.

My apartment to office used to be a kilometer apart. So by the time I would reach office, the Ikon used to be barely warmed up. Then, for the rest of the day, the car would be sitting in the parking lot. The cycle would repeat in the evening. As a result FE would be about 11.5-12.

Then the office moved to a different building and the home to office distance increased to eight kilometers one way. With the increase in commute, the car could warm up and sprint for a decent time. FE also increased to 13 to 13.5.
Yes Dot, more fuel is consumed in cold start. But in the drive cycles you have compared above, there chance that you drive the car in 5th gear is more in the 8 km stretch. So this could also be a factor in the fuel economy increase.
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Old 30th June 2011, 16:46   #27
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Default Re: How much fuel is consumed on engine start?

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Originally Posted by honeybee View Post
Does anyone have any evidence to prove a starter failed because of stopping and starting the engine repeatedly?If you assume a starter is designed for about 1,00,000 operations in its lifetime, and if I swithed my engine off and on about ten times a day, every day of the year, the starter would still serve about 27 years.
Starter never failed in my 5.5yrs ownership of my Ford Ikon. I used to switch off at signals and during major traffic jams that took a long time before we started moving.
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Old 30th June 2011, 17:11   #28
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Default Re: How much fuel is consumed on engine start?

One would be surprised to hear this.
I have seen advertisement where one can switch off if the wait time is around 15 secs or more to save fuel. This is applicable to all new cars with MPFI.
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Old 30th June 2011, 17:50   #29
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Default Re: How much fuel is consumed on engine start?

Really useful information here, just wondering what is recommendation for engine stoppage for diesel cars, particularly the ones with Turbo

It is recommended to keep engine idling for a minute at start to allow the spool of the turbo, does this mean we shouldn't be stopping engine unless the period > 60 secs. Any comments
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Old 30th June 2011, 20:15   #30
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Default Re: How much fuel is consumed on engine start?

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Originally Posted by Gansan View Post
Whether you push it or crank it, it will consume the same amount of fuel!
Tell me about it. My Vento petrol AT consumes fuel when I even THINK about it

Seriously though, how much fuel is actually consumed during start-up? Is it a function of the engine technology and environmental conditions or a constant amount? Fascinated to know...
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