I really don't like kickdown

Gazwould

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Been finding for months in the torquey 500Nm @ 1600-1800 rpm C250 CDI to just progressively squeeze the throttle not to trigger kickdown which takes time to decide and is then of a high revy nature of slower progress down to the peak torque that goes downhill at just 2000 rpm .

But it's not always a successful squeeze to avoid kickdown .

Would be nice not to have it and just floor the pedal , can it be disabled ?
 

whitenemesis

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Strange, I would have thought the car would only change down if that meant delivering the best from the engine to give rapid acceleration?
 
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Gazwould

Gazwould

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Kickdown usually drops a few gears , revs , changes up, revs , goes up to the gear you were in and pulls , then better progress is made.

They've probably done one TCU map for the 2.1 dervs and with one with a substantial amount available low down it accelerates well from 1K and doesn't need all this high rpm rubbish .
 
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Gazwould

Gazwould

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Yes, I prefer to drive on the torque so I'll feather the accelerator to stop it changing down.

So there might be more available if disabled as we're only using part throttle with success ?
 

rf065

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So there might be more available if disabled as we're only using part throttle with success ?
There's no need to disable anything, diesels should be driven differently to a petrol engine, there's no need to press hard on the accelerator ever. I can get very rapid acceleration in any gear by pressing the accelerator by half an inch and letting the torque do the work.
 

kid-jensen

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You sure you're actually getting kickdown (triggered by the kickdown switch or the sensing of full -throttle) rather than just causing the box to change down due to wider throttle openings?

It's easy to confuse kickdown with just a change-down which would happen at many throttle openings, not just pedal to the metal..

All manufacturers (but not Audi, apparently) arrange kickdown to give you the maximum acceleration AT THAT MOMENT and AT THOSE REVS and then continue to make changes at the correct point for max acceleration at the revs that it continues to receive (a few other subtleties affect it, but that's the basic principle). You ease-up just afterwards, and you are giving the box mixed-messages (ask the wife what they are).

It's amazing that autos are as good as they are with all the variables they have to juggle..

What you may have is the torquey low rev delivery gives you a certain kick in the back. That's what you want, but as the revs go up, torque drops off quickly (max may only be 2K revs or so) and the shove dies away. It's at this point that the box should change up, but so many manufacturers (I'm looking at you, Audi) make the engine crawl painfully around the rev-counter, before it changes, even though you are effectively slowing down.

The solution is to reprogramme the box for EXACTLY your torque curve, but I've had no luck finding anyone to do that to my old Allroad, which is why I now drive a Mercedes.
 

clk320x

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As DrFeelGood mentions it’s very easy to avoid engaging ‘kick down’..?
 
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Gazwould

Gazwould

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Got the same car and fully agree, when kick down the Rev go through the roof, would rather not have it but hey ho!!

That's the other thing I don't like , it revs to 4600 rpm , peak power is 4k as is most dervs , remapped it can be 3.5 K .

Absolutely ideal if it didn't kickdown and up change would be 4K or maybe earlier because peak torque is made so early .

I fully appreciate auto is a different way to drive with modulation to throttle input , but it's many years of driving a manual and I occasionally like full throttle !
 

rf065

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It sounds to me like your driving a diesel the same way you'd drive a petrol engined car. If you can get your head around that and modify your driving, you'll find it doesn't need anything done to it.
 
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Gazwould

Gazwould

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It sounds to me like your driving a diesel the same way you'd drive a petrol engined car. If you can get your head around that and modify your driving, you'll find it doesn't need anything done to it.
Been driving diesel for several years with a 1.9 PD .

If the car were a petrol , where the power band is higher this thread wouldn't exist .
 
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Gazwould

Gazwould

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^ As above , the people with the exact same car are in agreement .
 

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