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Old 18th June 2014, 22:30   #1486
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DSG shifts at redline in 'Sports' mode - is this the fastest way for diesels?

I had recently driven the new Jetta TDI DSG. Needless to say, I was impressed with the car and specifically the DSG gearbox. However one issue was a bit counter intuitive. In sports mode, the car holds on to each gear till its redline (~5100 rpm). But, doesn't the peak torque in diesels generally come at 2500rpm-3000rpm? Would holding on to each gear till the redline actually slow down the car compared to shifting at say 3000-3500 rpm???

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Old 19th June 2014, 01:33   #1487
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Re: Volkswagen Jetta : Test Drive & Review

Quote:
Originally Posted by AmolChaps View Post
Hi Rajat,

Sorry for the delay, I was out of touch for sometime. With regards to your question, I did go to the VW service station in Thane and discussed the problem. There was a extensive check carried out and they found out that the electrionic control valve on/near the compressor was faulty. As the car is in warrenty, they replaced it and now the AC works really well. A friend of mine who owns a Laura has also faced the same peoblem and changing the valve has worked for him also.
Try getting it checked. Hope this helps.

Amol
Hi! Amol thanks for the reply.
I'm yet to go to the vw service people for the checkup of my jetta, i hope i don't get to pay a huge amount for the damages, so fingers crossed.
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Old 19th June 2014, 08:35   #1488
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re: DSG shifts at redline in 'Sports' mode - is this the fastest way for diesels?

That way peak torque in a petrol also only comes in at around 4k revs. It would be extremely silly to wait for the peak torque, and then shift up just when you have it. Besides, you tend to shift up a little after you have achieved peak power in each gear
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Old 19th June 2014, 08:58   #1489
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Quote:
Originally Posted by petroguzzler View Post

But, doesn't the peak torque in diesels generally come at 2500rpm-3000rpm? Would holding on to each gear till the redline actually slow down the car compared to shifting at say 3000-3500 rpm???
Let's say that the peak torque comes at 3000 RPM but the DSG upshifts only at redline which is 5000 RPM. Once the upshifting is completed the RPM would fall to the peak torque range causing the engine to be on boil where acceleration will not be an issue.

But as you say if the car upshifts at 3000 RPM then once the upshift is completed the RPM would fall down to ~2000 RPM thereby loosing out on the power range causing longer acceleration time.

Simple answer is F1 engines, late shifting to stay in the power band most of the time.

Anurag.

Last edited by a4anurag : 19th June 2014 at 09:01.
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Old 19th June 2014, 15:59   #1490
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Re: Volkswagen Jetta : Test Drive & Review

Quote:
Originally Posted by petroguzzler View Post
I had recently driven the new Jetta TDI DSG. Needless to say, I was impressed with the car and specifically the DSG gearbox. However one issue was a bit counter intuitive. In sports mode, the car holds on to each gear till its redline (~5100 rpm). But, doesn't the peak torque in diesels generally come at 2500rpm-3000rpm? Would holding on to each gear till the redline actually slow down the car compared to shifting at say 3000-3500 rpm???

Note: If a similar thread exists, please merge it.
In the Jetta, as in the Laura, the peak torque comes in from 1750 to 2500. In sports mode, the engine redlines till almost 4800 and then the rpm drops to 2500-2700 and you would never feel the loss of power. The ECU is mapped/tuned such that the car revs a bit more freely in Sports mode than in the drive mode when both the DSG and the engine are a lot more relaxed.

Quote:
Originally Posted by a4anurag View Post
Let's say that the peak torque comes at 3000 RPM but the DSG upshifts only at redline which is 5000 RPM. Once the upshifting is completed the RPM would fall to the peak torque range causing the engine to be on boil where acceleration will not be an issue.

But as you say if the car upshifts at 3000 RPM then once the upshift is completed the RPM would fall down to ~2000 RPM thereby loosing out on the power range causing longer acceleration time.

Simple answer is F1 engines, late shifting to stay in the power band most of the time.

Anurag.
Beautifully explained Anurag!

Cheers
Rohan
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Old 22nd June 2014, 22:18   #1491
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Re: Volkswagen Jetta : Test Drive & Review

Dunno about all the details but the car has a dead spot at around 80-100 kmph. Has someone felt this?
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Old 22nd June 2014, 23:30   #1492
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Re: Volkswagen Jetta : Test Drive & Review

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Dunno about all the details but the car has a dead spot at around 80-100 kmph. Has someone felt this?
Can you explain it a bit in detail if you don't mind?

You mean like Turbo-lag types?

Anurag.
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Old 23rd June 2014, 06:33   #1493
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Quote:
Originally Posted by aseem View Post
Dunno about all the details but the car has a dead spot at around 80-100 kmph. Has someone felt this?
Manual or DSG?

By dead spot you mean the car takes time to move out of this slot? Even if you downshift?
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Old 23rd June 2014, 06:38   #1494
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I mean in dsg sports mode there is a dead spot where pace of increase becomes subdued like it has gone to turbo lag state but not quite.
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Old 23rd June 2014, 08:32   #1495
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Re: DSG shifts at redline in 'Sports' mode - is this the fastest way for diesels?

Quote:
Originally Posted by petroguzzler View Post
I had recently driven the new Jetta TDI DSG. Needless to say, I was impressed with the car and specifically the DSG gearbox. However one issue was a bit counter intuitive. In sports mode, the car holds on to each gear till its redline (~5100 rpm). But, doesn't the peak torque in diesels generally come at 2500rpm-3000rpm? Would holding on to each gear till the redline actually slow down the car compared to shifting at say 3000-3500 rpm???

Note: If a similar thread exists, please merge it.
The DSG in sport mode does not always hold the gear till redline, it depends on the throttle input, if driven with a light accelerator input DSG upshifts early and operates at lower rev band.
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Old 1st July 2014, 15:19   #1496
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Re: Volkswagen Jetta : Test Drive & Review

Moderatore note: Removing [Font] tags, please avoid copy paste from external font editors. Also do a Preview before Submitting posts. Thanks.


Hi,
Today something strange happened with my Jetta Diesel (2013 - Highline). I was heading to office and on the way I heard continuous clicks in the left side door panel. Seemed as if the door was trying to lock itself but could not. I checked the door lock buttons on the driver side door panel. The background illumination had gone which confirmed my fear about malfunction in the central locking system. As soon as I reached office I checked and figured out that the left front door was not locking. All the other doors lock well including the boot.
Although I will get the car to service center tomorrow, but if there is any immediate solution then it will be a relief for me as currently my car is vulnerable and security is compromised.
I wonder what happens when you are in the middle of nowhere and something like this happens. I guess these are pitfalls of complicated electronics in a machine and ignorance on my end.
Thanks in advance.

Amol

Last edited by Jaggu : 1st July 2014 at 15:36.
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Old 1st July 2014, 16:14   #1497
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Re: Volkswagen Jetta : Test Drive & Review

Can you try to lock the left front door specifically using the key?
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Old 1st July 2014, 17:16   #1498
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Re: Volkswagen Jetta : Test Drive & Review

Quote:
Originally Posted by AmolChaps View Post
Although I will get the car to service center tomorrow, but if there is any immediate solution then it will be a relief for me as currently my car is vulnerable and security is compromised.
I wonder what happens when you are in the middle of nowhere and something like this happens. I guess these are pitfalls of complicated electronics in a machine and ignorance on my end.
Thanks in advance.

Amol
Hi Amol,

I doubt if any other alternative is possible since door lock / unlock is centralized and controlled by driver only (all five actuators controlled together). You have to take it to service centre. It could be either the actuator or the connector.

If you have any good accessory shop near by, you could get the door panel removed and check the connector..

All the best. Please update..

Last edited by Chethan B G : 1st July 2014 at 17:17.
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Old 2nd July 2014, 10:32   #1499
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Re: Volkswagen Jetta : Test Drive & Review

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Originally Posted by anandpadhye View Post
Can you try to lock the left front door specifically using the key?
Unfortunately that is not an option. There is no key hole and as the locking system is electronic only, manual is not an option.
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Old 2nd July 2014, 13:52   #1500
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Re: Volkswagen Jetta : Test Drive & Review

Will this help?






Last edited by anandpadhye : 2nd July 2014 at 13:55.
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