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Old 18th September 2008, 17:30   #16
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If you do not use Turbo for first two KM and last two km of your car starting and stopping respectively (If you stick to <1800 rpm -in most cars) your turbos are safe. Following this is more easier than having to idle the car for a minute each time you start or stop.
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Old 18th September 2008, 18:57   #17
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could you share the source of the same?
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Old 18th September 2008, 18:57   #18
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Quote:
Originally Posted by Steeroid View Post
Dude, there is NO place in the car that I havent seen and that includes the underside...NO sticker on the Dicor. Period.

The only sticker they've put on is one by the drivers side of the windscreen which relates to the usage of 4WD and how to shift back to 2WD.

Pg 133 of the 2.2 Dicor owner's manual.
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Old 24th September 2008, 08:59   #19
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Turbo idling

Hi Steer- The manual recommends a minute idling at the start and switch off. Its mentioned in the owner manual..safari dicor 2.2

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Originally Posted by Steeroid View Post
I'm a bit concerned here - the Safari Dicors manual doesnt suggest this kind of idling, not does it carry a sticker that says its required. I've seen this sticker on the older Scorpio though...I still idle the vehicle before and after use, though.

However, even after idling for say a minute or so there's a very distinctive hum of a turbine winding down AFTER the engine has stopped...

On the Smart, I can hear the water pump humming away for about 1/2 a minute after I stop the engine.
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Old 29th September 2008, 02:46   #20
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I try and follow the 1 minute before start and shut off regime. Often it becomes 40 seconds. I also try and avoid getting into turbo region while the engine is still cold but its not always possible. Sometimes I even move for a short distance without pressing the accelarator to compensate for less idling before and after shut-off.

The user's manual of the Palio Multijet recommends idling "for a while" before shutting off "after a taxing drive". Talk of being vague!!

However, I am keen to know the following, especially in the light of real world situations:

a. Does this mean you can't shut off the engine at traffic lights (Nobody can idle for a minute, shut off and then restart and idle for a minute before moving!)

b. Occassionally, I do not idle before moving in case the Temp Gauge is well above the cold mark (engine is still warm and has not been shut for a long time) but definitely idle for 30-40 seconds before shut off. Is this safe practice?

c. Apart from a blown turbocharger, does not following the idling practice affect any other part of the engine or performance?

d. If this practice has not been followed religiously for 9000 kms, is it too late to start ?
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Old 29th September 2008, 09:33   #21
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We have to understand why they ask for 30 sec idling of Turbo, its for the lubrication at start and to prevent oil coking in the turbo at shutdown.

If you drive sanely at start and before shutdown, this might not be required. Also at traffic stops the turbo is already greased if you shutdown and plan to start within a few minutes.

Quote:
Originally Posted by architect View Post
I try and follow the 1 minute before start and shut off regime. Often it becomes 40 seconds. I also try and avoid getting into turbo region while the engine is still cold but its not always possible. Sometimes I even move for a short distance without pressing the accelarator to compensate for less idling before and after shut-off.

The user's manual of the Palio Multijet recommends idling "for a while" before shutting off "after a taxing drive". Talk of being vague!!

However, I am keen to know the following, especially in the light of real world situations:

a. Does this mean you can't shut off the engine at traffic lights (Nobody can idle for a minute, shut off and then restart and idle for a minute before moving!)

b. Occassionally, I do not idle before moving in case the Temp Gauge is well above the cold mark (engine is still warm and has not been shut for a long time) but definitely idle for 30-40 seconds before shut off. Is this safe practice?

c. Apart from a blown turbocharger, does not following the idling practice affect any other part of the engine or performance?

d. If this practice has not been followed religiously for 9000 kms, is it too late to start ?
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Old 22nd March 2010, 16:20   #22
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I am just attempting to find whether engine-idling for saving the turbo is worth (Please correct me if my calculation is wrong):

My average distance per journey = 15 km (this is the one-way distance to my office, i.e the distance between start and stop of the engine).
Engine Idle time needed = 1 minute just after start and 1 minute just before stop. i.e, total 2 minutes.

That means 2 minutes of idle time for 15 km, or 4000 minutes of idle time for 30000 km.

Assume 1 km worth of diesel wasted for 3 minutes of idling.
(Source: http://www.team-bhp.com/forum/owning...ml#post1777725)
This means for 4000 minutes of idling, you waste 1333 km worth of diesel.

Assuming a mileage of 10 km/liter for Scorpio, your wastage is 133 liters of diesel. If diesel is 35 Rs/Liter, your wastage is Rs 4655.

I don't know the cost of replacing the Turbo, or how many kilometers a turbo lasts without idling, so please help me in this calculation.

PS: This also means that if your average distance per journey is only 5 km, you would waste diesel worth Rs 13965 for idling over a distance of 30000 km.

Last edited by jinojohnt : 22nd March 2010 at 16:28.
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Old 22nd March 2010, 16:29   #23
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typically one would need to slow down a bit for the last couple of kilometres before one reaches one's destination. this enables gradual cooling of the turbo charger unit.

if one has revved hard or driven very fast for a good distance and then one is coming to a stop, it is a good idea to allow the turbo to cool down by idling for 30 sec to a minute.

In city traffic situations typically one doesnt get to drive at such speeds anyway and given our scene in Bangalore the roads are pretty bad so going fast causes passenger discomfort. Hence, since the Turbo is not being spooled up all that much, if one goes slow for a km or two before coming to a dead halt, the idling may not strictly be necessary.

Additionally, on the old Scorpio (Non Crde) and in the current Bolero DI Turbo, there is that yellow sticker which advises one to idle for a minute before switching off completely.
In the newer Scorpios and as far as I know, in the Bolero Crde Storm, this particular yellow sticker doesnt exist.
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Old 22nd March 2010, 16:32   #24
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The point of the idling is not to turn on the turbo immediately after starting, when it is not sufficiently lubricated, and similarly about stopping.

What I do is drive at near idle revs for a minute immediately after starting/before starting.

works the same
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Old 22nd March 2010, 17:02   #25
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Now I have a question, how does the Scorpio diesel-electric hybrid handles this idling thing?
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Old 22nd March 2010, 17:09   #26
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You need not be stationary while idling. for example, when you are driving out of your aparment complex, or backing out of the driveway, you can do so with nill acc pedal input. Most turbo diesels can idle along in second gear without issue.
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Old 22nd March 2010, 17:18   #27
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Idling with turbochargers

Quote:
Originally Posted by shankar.balan View Post
In the newer Scorpios and as far as I know, in the Bolero Crde Storm, this particular yellow sticker doesnt exist.
But still you have to adhere to the thumb rule.

Quote:
Originally Posted by greenhorn View Post
The point of the idling is not to turn on the turbo immediately after starting, when it is not sufficiently lubricated, and similarly about stopping.
Rightly said.

Quote:
Originally Posted by tsk1979 View Post
You need not be stationary while idling. for example, when you are driving out of your aparment complex, or backing out of the driveway, you can do so with nill acc pedal input. Most turbo diesels can idle along in second gear without issue.
This is called as Low idle governing, which is achieved through PID controllers.

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Old 22nd March 2010, 17:22   #28
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How do you stick to the thumb rule in a micro-hybrid? Here the moment you put car in neutral, engine will shut off
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Old 22nd March 2010, 17:32   #29
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the engine shuts off only after a certain time duration (5 secs IIRC), micro hybrid is actuated usually in city driving conditions where the turbo is not revved to higher limits, also you need not idle for 30 secs once you start after a engine shut off as the turbo is sufficiently lubricated at that time,

Spike

Last edited by SPIKE ARRESTOR : 22nd March 2010 at 17:36. Reason: add info
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Old 22nd March 2010, 19:37   #30
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Quote:
Originally Posted by shankar.balan View Post
In the newer Scorpios and as far as I know, in the Bolero Crde Storm, this particular yellow sticker doesnt exist.
Nope the Bolero Storm has the yellow sticker demanding 1 minute but the manual says atleast 20 seconds
Quote:
Originally Posted by SPIKE ARRESTOR View Post
But still you have to adhere to the thumb rule.
What is the thumb rule?

I generally idle for a minute in the morning when doing an absolute cold start and do about 20 seconds in subsequent start. Is that enough. Also wanted to know that is there anything like bedding for a turbo like you have for engines?
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