2019 Rapid 1.5 TDI Diesel DSG sluggish upshifts during uphill ascent , inclination sensor issue ?

[PassionateAboutCars]

I own a Skoda Rapid Diesel Automatic, 2019 model. It has DQ200 Gearbox. I also see the exact same issue.

 

Seems the gear shift behaviour is different in Flat roads and bit uphill roads.  Gearbox holds on to the lower gears little longer than on flat surface. Mine is a brand new car which is just 7 months old and i see exact same behavior. And it is always seen during uphill. 

 

It spends close to 2500rpm in 2 gear and then it shifts to 3 gear. This is with just the driver and no other load in the car. And the speedometer is around 35 to 40 Kmph.

I'm seeing such a behavior even in 3 gear as well. So it seems "upshifts" are sluggish.

[Ootohere]

Welcome to the forum.

Your 1.6TDI & 7 speed twin dry clutch DQ200 DSG might just be behaving as it would be expected to and really can not be compared to a 2.0TDI 6 speed wet clutch or 7 speed wet even if they are faulty.

[PassionateAboutCars]

Actually, it's 7 speed dry clutch dq200 gearbox. Its 1.5 tdi . 2019 variant. 

 

Issue is, the gearshifts during uphill ascent is sluggish, than compared to horizontal roads. And I hear engine roaring and it's annoying. Now the problem statement is :

 

 

"Why can't they have same behaviour as on flat roads  Nice and quick. ?"

 

Its D mode by the way. Not sports mode.

[Breezy_Pete]

Gravity?

 

[PassionateAboutCars]

When the engine rpm begins to increase beyond 2500 rpm in 2 gear means that it's time to upshift, what's the point in revving high and allowing to increase without upshift, because rpm will only increase if load is compensated. 

 

I put to tiptronic mode and upshift as a work around. 

 

May be simple sensor inclination calibration issue ?

[langers2k]

7 minutes ago, PassionateAboutCars said:

When the engine rpm begins to increase beyond 2500 rpm in 2 gear means that it's time to upshift,

 

Erm, it doesn't, otherwise the redline would be at 2500 rpm

 

8 minutes ago, PassionateAboutCars said:

what's the point in revving high and allowing to increase without upshift 

 

Because the ECU has decided there is still enough load on the engine to hold the lower gear.

 

9 minutes ago, PassionateAboutCars said:

May be simple sensor inclination calibration issue ?

 

Seems unlikely, mostly as I think your car is probably working normally...

 

You might be better posting in the Rapid section as a 2019 Rapid is very different to a MK2 Octavia in terms of engines and electronics. At least it'll let you compare to other similar cars

[J.R.]

No information from inclination sensors (which exist but for other reasons) is used to determine shift up points, its simply a comparison of the throttle position and the acceleration, on the flat the vehicle will accelerate quicker for a given throttle position than on a hill and hence the gearbox will short-shift the upchanges on partial throttle.

[PassionateAboutCars]

I own a Skoda Rapid Diesel Automatic, 2019 model. It has DQ200 Gearbox.  I'm facing the below issue, any suggestions are welcome.

 

Issue:

It seems the gear shift behaviour is different in Flat roads and bit uphill roads (even moderately uphill, in city conditions) .  Gearbox holds on to the lower gears little longer than on flat surface. Mine is a brand new car which is just 7 months old and i see it during uphill ascent. For instance, It spends close to 2500rpm in 2 gear and then it shifts to 3 gear, this is with just the driver and no other load in the car. And the speedometer is around 35 to 40 Kmph. I'm seeing such a behavior even in 3 gear as well. So it seems "upshifts" are sluggish.

 

The engine roars and it is audible inside the cabin. This is annoying and to get rid of it, as a workaround, i change to tiptronic mode and upshift.

 

Why is this behavior seen in DSG variant ? Is it related to "inclination sensor" calibration issue ?  I have also tried to lift off my foot momentarily from accelerator after it leaches 2500 rpm, but it never upshifts. 

Seems the thresholds for upshift during uphills is not properly calibrated. 

 

Actually, it's 7 speed dry clutch dq200 gearbox. Its 1.5 tdi . 2019 variant.    Now the problem statement is :

 

 

"Why can't they have same behaviour as on flat roads  nice and quick  ?" 

Its D mode by the way. Not sports mode.

 

I dont see any point in holding the gears and revving the engine up and delaying upshifts. Seems it is holding the torque which we are not requesting for .  Like i try to lift off my foot from accelerator momentarily after it reaches a roaring rpm of 2500rpm in 2 gear, but it never up****s. 

 

 

 

 

 

 

[Ootohere]

@PassionateAboutCars

You posted your question in the Rapid Project section not the Rapid section.

 

I had no idea that there was a 1.5TDI available.

Is it the same as in this video?

 

Looking at a 3 & 4 year old review you maybe got performance and behaviour wise exactly what Skoda engineered and supplied. 

 

 

 

 

 

 

Edited 30 July, 2020 by Roottoot

[PassionateAboutCars]

@Rootoot

Yes, it's the same rapid. Its launched 4 years back.  I purchased this model  so that all the issues in dsg  transmission  would have been fixed and will be well tested. 

 

@J.R.

Definitely, if acceleration / throttle position only thing that is used, then during uphill ascents , it revvs higher. They should have had a different torque curves uphill. So that it shifts aptly and not rev hard.

 

The same rapid with manual gearbox is quicker than dsg variant during uphill. 

 

Delayed upshifts will make the car travel slower. 

[PassionateAboutCars]

 

@J.R.  To over simplify the problem, imagine having just one gear in the car and a powerfull engine of 2 litre , this car can be defeated easily by 800 cc car with 5 speed transmission.

 

   We don't need that much of torque to carry 4 people uphill, it should upshift. 

[Breezy_Pete]

16 minutes ago, PassionateAboutCars said:

 

 

   We don't need that much of torque to carry 4 people uphill, it should upshift. 

You must do, otherwise it would.

[john999boy]

Topics in different locations now brought together in the correct place.

[PassionateAboutCars]

1.5 TDI with 250 Nm torque is no less. 

DSG sw which decides about upshifting during uphill ascent seems to be the cause for this issue. 

 

Holding gears longer than necessary is irritating.  I have raised this concern with Skoda. 

[PassionateAboutCars]

The torque curve in 1.5TDI engine falls after 2500 rpm.  As per their specification, it is 250 Nm between 1500 rpm till 2500 rpm.

So no point in holding the gears past 2500 rpm expecting the car to accelerate. It won't.  So, it makes sense to upshift so that rpm falls abruptly and expect for better acceleration.

 

The Torque curve ( Torque vs RPM) is not linear. 

[Breezy_Pete]

What about the power curve? Can you post an image of both? Or link to these data?

I would expect it to be power that's needed to get up hills.

[PassionateAboutCars]

[PassionateAboutCars]

Skoda rapid 1.5 diesel model is discontinued in India due to BS6 standards which took into effect from 2020 April. So, Skoda official website doesn't have this model.  Sorry, I didn't find any official links. 

[PassionateAboutCars]

And fyi, the use case or issue is seen even with only driver in car with no load. And it's with in city limits not very steep up hill road. 

[Breezy_Pete]

Peak Power at 4000rpm in that table.

[PassionateAboutCars]

Hmm. Ok. Thanks @Wino

 

Its getting involved. 

 

Wondering why it needs so much power to climb in moderate uphill with just one person in car. 

 

Use to drive manual diesel 1.3 litre engine  for couple of decades. Never revved it so hard to climb the hill, even under full load. 

 

 

Need to understand criteria for upshifts clearly. 

 

 

 Power (kW) = Torque (N.m) x Speed (RPM) / 9.5488

 

 

Edited 1 August, 2020 by PassionateAboutCars

[PassionateAboutCars]

May be acceleration is measured by accelerometer sensor and till the level is achieved it revs up and hold on to lower gears.  Those request levels are mapped onto pedal. 

 

But wondering why we tend to upshift a manual car thinking it is appropriate. 

[Phil-E]

I really don't think this is a problem.

 

There are more factors involved than just how much power is required to climb a hill.

 

Yes the car probably could climb the hill in the next gear up, but they're not tuned that way (from a software point).

 

The whole point is that keeping it in a higher gear can labour the engine, increase soot into the DPF, Put extra Stress on gearbox and clutches etc etc.

 

It's just like driving a manual where you would change down a gear to go up a hill or should do).

 

The gearbox does in fact also use the inclination sensor. When driving down hills it's will also downshift to increase engine braking and reduced the need to use the brakes. I believed the coasting function that some DSGs have is also disabled while going down hill.

[Phil-E]

And as for the shift points of the gearbox there is more taken into account than just throttle position:

 

Throttle position, engine load, hill gradient, engine revs, vehicle speed, engine temperature, DPF soot level (regen currently occuring etc), battery voltage, AC load etc etc.

[PassionateAboutCars]

Thanks @Phil-E

 

I have given it to Skoda service center. I will post the their justification here once I get it. 

 

Mine is a BS4 , same as Euro 4 car. No DPF in my car anyways. 

 

Makes sense, there could be 'n' number  of parameters involved in upshifts. Have observed downhill, it uses engine braking.