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Old 5th November 2008, 17:23   #16
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Originally Posted by shuvadips View Post
Yeh its perfectly normal, I remember when my driving school instrutor told me so, I was so surprised.

I thought its just like the bikes whenre to make it move from stationary you need to release the clutch slowly & press the accelerator slowly in a synchronous way.
There are older vehicles, wherein you have to use your right foot for both brake and accelerator simultaneously, just because you cannot release the clutch without throttle and you cannot also release brake without some throttle as in slopes.

I think that it is an intentional design by the manufaturers that idling speed for modern car engines is quite capable of pulling the car with half clutch and without throttle.

Having said all that, petrol experience is still not same as diesel experience. I still have to work up a little bit more on slopes with petrol engines.
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Old 5th November 2008, 17:49   #17
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This is normal and quite desirable too. If the car creeps at slow speed without pressing accelerator you're almost having the benefit of automatic transmission!

Most modern petrol engines do not stall easily. When ECU detects creeping, it feeds enough fuel to engine so that it produces just enough torque to prevent stalling - so the car creeps forward.

Diesels inherently produce more torque so they do it all the time.
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Old 5th November 2008, 17:57   #18
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It is true, the car pulls without giving acceleration in even steep slopes. I have experienced it always.

There is something more I have to add. In my car, at a slope near my home, everyday I have experienced this. When the car is climbing the slope (usually in 3rd gear), and if I try to give acceleration at slow speeds, the car stalls. If I dont touch the accelerator pedal, the car manages to creep up without stalling. How is this?
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Old 5th November 2008, 18:14   #19
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Originally Posted by abhilash_iv View Post
If I dont touch the accelerator pedal, the car manages to creep up without stalling. How is this?
That is not normal. If the engine is able to pull with clutch fully released in a given gear, throttling it should just pull it faster.
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Old 5th November 2008, 18:20   #20
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abhilash_iv@ I dunno the reason, but I feel that I have also experienced similar scenario. However it depends on how you use the accelerator.
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Old 5th November 2008, 19:39   #21
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This is fairly, a normal situation : without gas and off the clutch the car rolls, in higher gears it will stall ( all depends on the torque delivery of engines at low end, diesels are kings). As for rolling back in an incline I dont think its possible with the 1st or 2nd gear engaged. At the most the car will stall and whille declutching you might have a roll back.
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Old 5th November 2008, 19:52   #22
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Now you know why they say torque is cheap....



Quote:
Originally Posted by Rehaan View Post

Deisels have much better low-end torque, and hence can lug much better in situations like this.
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Old 2nd May 2013, 19:08   #23
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Default Help required for Hundai I-20, doubts.

Dear all,

I am very much into Jeeps and cars is not my scene, it would not be appropriate for me to answer the questions posted by my friend Mr. Max Ali from Hyderabad.

Hence, I seek the esteemed help of fellow BHP'ians who own an I-20 and are experiencing the same or otherwise. Also ones who are technically empowered to help my friend, your valuable help is highly appreciated.

Thanks you in advance, below is the quote from my friend.
Regards,

"Dear Adil Sir,

I need some help with a problem I have discovered with my Hyundai I-20 and since you are on BHP perhaps you can ask your colleagues if anyone else has also encountered the same problem. Talwar Hyundai claims that there is no problem but I disagree.

I have a I-20 Asta-Navi 2012 model with 6600km. I bought it brand new. When driving I noticed that the vehicle while in 5th gear does 40-45kmph on its own without the need to press the accelerator. Almost like it is on cruise control and this vehicle/model does not come with cruise control. The vehicle is not advanced/revving high when I press the clutch so this behaviour is very odd.

Talwar Hyundai kept the car for two days and then returned it to me stating that there is no problem. I believe that they are lying as their GM of Service went on a test drive with me and confirmed that this car drives itself without the need to press the accelerator.

One of the guys at Talwar Hyundai told me that there is a added feature that helps provide better gas mileage and if I were to tap on the break the vehicle will slow down on its own and not keep accelerating. This is wrong and they would not give this to me in writing. I drove the entire length of Necklace road from Prasad's circle to Ranigunj without ever touching the accelerator and I have tapped on the brakes and the vehicle will gradually speed up to hover in the 40-45kmph range.

Any help that you can provide in the form of similar experience or have any existing I-20 owners of 2012 model year, drive their vehicle and have them take the foot off the accelerator on an open road and see if they can also enjoy the same cruise control benefit.

Thanks in advance for your help.

Rgds,
Max Ali."

Edit: the length of 'Neclace Road' from Prasad's circle to Ranigung is about 10 kms.

Last edited by fazalaliadil : 2nd May 2013 at 19:11.
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Old 2nd May 2013, 19:26   #24
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Default Re: Help required for Hundai I-20, doubts.

I think this is pretty normal behaviour for most cars, AFAIK any car that's in perfect mechanical condition, starts rolling as soon as you let go of the clutch pedal!
Throttle or no throttle doesn't make a difference, the only thing that matters is that you need to be careful while releasing the clutch pedal so as not to stall the car.
Moreover I think all cars can cruise at those speeds in the fifth gear, with out any throttle input.

I don't think this is a defect or something!
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Old 2nd May 2013, 20:03   #25
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Default Re: Help required for Hundai I-20, doubts.

Adil Sir,

This is the Low Idle Governor at work.

Basically, for all ECU controlled engines, the ECU is programmed to hold onto a min RPM (around 850-950) to prevent the engine from stalling.

If the clutch is released suddenly, the engine generally is not able to take on the load and the car stalls. However, if you release the clutch gently, the LIG comes into play and prevents the car from stalling.

This feature is present on all modern cars(both petrol & diesel). This was indeed fun for me as well moving from Mark4 Ambys to MPFI Zen and Punto & Spark until my friend from Bosch explained the working of this

The car is perfectly fine and is doing as expected.

p.s.: Even my Punto does around 45-50kmph in 5th gear without accelerator input.
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Old 2nd May 2013, 20:06   #26
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Default Re: Help required for Hundai I-20, doubts.

You didn't mention if its a diesel variant or the petrol, or I missed that part?

Anyways its normal behavior in most of the diesel cars. Call it the low end torque or the anti-stall-mechanism. Every gear will have its own minimum speed and 5th usually has 40-50 km/hr. These days some petrol cars also behave this way.

BTW you are a jeeper, you should know that better, Don't you use only the clutch to make your diesel jeep start rolling from stand still? Though in the old jeeps, its the torque which makes them moving.

Last edited by tbppjpr : 2nd May 2013 at 20:09.
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Old 2nd May 2013, 20:28   #27
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Default Re: Help required for Hundai I-20, doubts.

Quote:
Originally Posted by tbppjpr View Post
You didn't mention if its a diesel variant or the petrol, or I missed that part?

BTW you are a jeeper, you should know that better, Don't you use only the clutch to make your diesel jeep start rolling from stand still? Though in the old jeeps, its the torque which makes them moving.
Sir,

I have no idea about the fuel variant, can get back on that info.

Sorry, I am a beginner and learning.
Regards,
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Old 2nd May 2013, 20:40   #28
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Default Re: Help required for Hundai I-20, doubts.

Quote:
Originally Posted by fazalaliadil View Post
Sir,

I have no idea about the fuel variant, can get back on that info.

Sorry, I am a beginner and learning.
Regards,
In addition to the fuel type please get this info too -- 1) The RPM in 5th gear while its on this strange auto cruise mode and 2) The idle rpm of the car

Last edited by Sankar : 2nd May 2013 at 20:42.
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Old 2nd May 2013, 21:21   #29
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Default Re: Help required for Hundai I-20, doubts.

I think it is normal. Even my Chevy Spark does around 40kmph in the 5th gear without any input from the accelerator.

Once you leave the clutch slowly in 1st gear the car starts moving gradually and the speed increases gradually with every gear change.

But I think you should still update the thread with what rpm does the i20 do 50kmph on its own.
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Old 2nd May 2013, 22:05   #30
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Totally normal. And it's not only for 5th gear, try at gear 1, 2, 3 & 4 too, they all have certain speeds at which the car will keep running without any throttle input.

Wonder, why didn't service center share it as normal behavior with any car.
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