Fuel Efficiency Figures of Your Cars


#241
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hemantp

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VivekRj.Dieselhead said:
City Mileage i got yesterday in the morning.
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That is great!

So the "up-shifting at 1500 rpm" is helping you?

I have also seen letting the rpm fall below 1200 (or may be 1000) mark leads to more fuel consumption, at least going by instant readings.

For example, doing 40 Km/hr in 4th gear @1500 rpm gives better mileage than doing same speed in 5th gear @1000 rpm.

Is the above expected? What could be the explanation?
 
#242
sethumurugan

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hemantp said:
That is great!

So the "up-shifting at 1500 rpm" is helping you?

I have also seen letting the rpm fall below 1200 (or may be 1000) mark leads to more fuel consumption, at least going by instant readings.

For example, doing 40 Km/hr in 4th gear @1500 rpm gives better mileage than doing same speed in 5th gear @1000 rpm.

Is the above expected? What could be the explanation?
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Friend, Can you pls explain me that part. I sometimes do in low rpm at higher speeds assuming that always lower rpm consumes less fuel.
 
#243
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hemantp

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I was (still am) also of the same understanding that lower rpm = better mileage, but I ended up having some diffelrent readings in my recent highway trip so wanted to confirm.

generally I tend to reach and keep to 5th gear as early as possible for exact same reason, still wanted to check.

But ooking at instant consumption readings 2/3 days back, I found the above observation not holding true in some cases, especially the one I mentioned.

IIRC, 5th gear @1000 rpm, the reading was as low as 14 or 16 km/l (not so sure now but will try again sometime), while 4th gear @1500 rpm, it was ~30 km/l (+/- 2 km/l).

In both cases, I tried to be *very* light on the accl pedal - enough to maintain the respective rpm (but possible that's where the catch is).
 
#244
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MSN1

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#244
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Am using figo diesel and the city mileage will be around 15 to 16 kmpl

what am doing is to try stay with in 1500 to 2000 rpm and use the clutch wisely

* on a empty stretch or low traffic road where my speed is around 60 then if the road is flat or down i will fully apply clutch and take my foot away from accelerator and be ready to apply break any time
* avoid using half clutch to increase speed faster
 
#245
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juandiazmora

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hemantp said:
I was (still am) also of the same understanding that lower rpm = better mileage, but I ended up having some diffelrent readings in my recent highway trip so wanted to confirm.

generally I tend to reach and keep to 5th gear as early as possible for exact same reason, still wanted to check.

But ooking at instant consumption readings 2/3 days back, I found the above observation not holding true in some cases, especially the one I mentioned.

IIRC, 5th gear @1000 rpm, the reading was as low as 14 or 16 km/l (not so sure now but will try again sometime), while 4th gear @1500 rpm, it was ~30 km/l (+/- 2 km/l).

In both cases, I tried to be *very* light on the accl pedal - enough to maintain the respective rpm (but possible that's where the catch is).
Click to expand...
It depends on the engine load.. For example: when you are on 4th gear at 40 km/h the engine is at 1500rpm where it has an ideal torque (on diesel engine) so the engine is comfortable at that speed and need only 10% of the power, so it inject a little portion of fuel. But when you are on 5th gear at the same speed, the engine runs at 1200rpm, where it has less torque so need increase the amount of fuel injected to produce enough power to maintain that speed.

To get better mileage you should equilibrate between how much power you need and how much torque the engine has at that RPM, it's a waste of money doing 30km/h at 5th gear, because at that rpm the engine has no torque, so it need 100% of the power to maintain that speed and the ECU calculates that needs a full throttle to do that, and inject all the fuel possible..
 
#247
sethumurugan

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juandiazmora said:
It depends on the engine load.. For example: when you are on 4th gear at 40 km/h the engine is at 1500rpm where it has an ideal torque (on diesel engine) so the engine is comfortable at that speed and need only 10% of the power, so it inject a little portion of fuel. But when you are on 5th gear at the same speed, the engine runs at 1200rpm, where it has less torque so need increase the amount of fuel injected to produce enough power to maintain that speed.

To get better mileage you should equilibrate between how much power you need and how much torque the engine has at that RPM, it's a waste of money doing 30km/h at 5th gear, because at that rpm the engine has no torque, so it need 100% of the power to maintain that speed and the ECU calculates that needs a full throttle to do that, and inject all the fuel possible..
Click to expand...
Man that is very clear. Thanks.
 
#248
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hemantp

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juandiazmora said:
so need increase the amount of fuel injected to produce enough power to maintain that speed.
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Perfect, thanks. Matches exactly with the observation I had.

In all, since the 4th vs 5th gear observation I have decided to up shift only @2000 and maintain around 1700 rpm otherwise.

I suppose it should give best combination of performance + fuel efficiency + driving comfort. But guess will be different for each car, e.g., even for 90 HP (VGT) punto, this could be different so will be for Figo, Polo, Vento, Linea etc.

What do experts say?
 
#249
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MSN1

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MSN1 said:
Am using figo diesel and the city mileage will be around 15 to 16 kmpl

what am doing is to try stay with in 1500 to 2000 rpm and use the clutch wisely

* on a empty stretch or low traffic road where my speed is around 60 then if the road is flat or down i will fully apply clutch and take my foot away from accelerator and be ready to apply break any time
* avoid using half clutch to increase speed faster
Click to expand...
This is with full A/C and shifting at close to or around 2000 rpm

not just that fuel efficiency depends on several other factors also, which our experts can able to tell
 
#250
Lucas

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Driven 310 kms.fuel consumed 17lits. Got 18+. 100%highway.little AC use. Most of the time drove @80-90kmph.
 
#251
amiti

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first tank full update of my toyota liva diesel.
16.17 kms/lit 100% city driving. No use of 5th gear till date. 100% usage of AC.
I hope it will improve. Sales people say, it should give me around 18+in city after few thousand kms.
 
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#253
Figoian

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Done with 5th Service (40K) on Friday and had a Road Trip to Yelagiri. The FE isn't improved in anyway even after the service. The FE was 15.3 KMPL.

Metro Ford is suggesting for a Mileage Test, however, I am not sure would that be the best way to find it.


amiti said:
first tank full update of my toyota liva diesel.
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Amit - Congrats on the new acquisition.
 
#254
Releesh

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juandiazmora said:
It depends on the engine load.. For example: when you are on 4th gear at 40 km/h the engine is at 1500rpm where it has an ideal torque (on diesel engine) so the engine is comfortable at that speed and need only 10% of the power, so it inject a little portion of fuel. But when you are on 5th gear at the same speed, the engine runs at 1200rpm, where it has less torque so need increase the amount of fuel injected to produce enough power to maintain that speed.

To get better mileage you should equilibrate between how much power you need and how much torque the engine has at that RPM, it's a waste of money doing 30km/h at 5th gear, because at that rpm the engine has no torque, so it need 100% of the power to maintain that speed and the ECU calculates that needs a full throttle to do that, and inject all the fuel possible..
Click to expand...
For better Mileage, Are different driving styles need for the normal petrol engine and the turbo diesel engine?

I am asking this because, When ever i had discussion regarding the mileage with one of my friend who owns a new model swift diesel, he tells that the ASS guys told him to rev in each gear to get a good mileage. he is doing the same in each gear and while riding in his car, i can feel the turbo works in each gear. but this makes me riding with him uncomfortable.each gear shift effect the passengers. he is getting an overall 15-18 km/ltr mileage with A/c. But i feel this is less for this car. On My esteem type 3, i am getting 14-15 km/ltr with A/c in my driving style (i'm a sedate driver and mostly my car will be under 2K rpm on my driving) and when he driven my car for a 200 km trip, 12 Km/ltr is the mileage we got.
 
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