Mircea

Hi all,

My RS pulls clearly harder when I reduce the throttle, for a second or two, then comes back to normal. It happens especially after a hard acceleration and always when you want to brake fast
Anyone noticed the same behavior? Mine did that form day one but now is more obvious than before.
Any solution?

Thanks,
Mircea.

TaviaRS

Mind used to do the same. Now cured by the remap.

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Fabpreza

.... also cured with my 4x4 remap. I'd actually forgotten until now that it used to happen.
(Emissions related - Impreza Turbo had a noise control routine which behaved similarly - reduced boost)

greg2302

Mine seems to pull better if I don't actually floor it ..... but I don't think we're talking about the same thing here, are we ?

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An idiot is somebody who persists in holding their own opinion even after I have enlightened them with mine

Mircea

It may be the same thing.... Mine does the same, but only for a limited amount of time, 10s or so, after that you should floor it again. However, after 4500-5000 rpm I need to keep it floored for maximum power.

There is any procedure to realign the accelerator module (something similar with throttle body alignment)?
Can you see with VAG-COM or other tool the value (a percentage will be the best) that accelerator module is sending to the ECU?

Mircea.

Dutch4x4

Similar experience as Greg's here. A slightly more delicate touch gives more wollop. Flooring it will often lead to ECU rethink or even the wastegate opening - probably the standard chip treatment as opposed to a remap.

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Mrs D's Briskoda: Octavia 4x4 turbo (2003), Oettinger 210, Koni Sport, MAD Sportive, Dotz Le Mans 17", Bridgestone Potenza S-03, sports interior. And a Fiesta ST (2006) for myself...

TaviaRS

Yep, its almost like a time delay if you use full throttle. Once the boost gauge was fitted I noticed UI got more boost on 1/2 throttle than if I tried to mash it thought the floor boards

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A jolly sensible Mercedes E class saloon in a rather fetching bluey grey colour. No it isn't fast, no it isn't modded, and yes, it will still eat your Fabia for breakfast.

Official mobile chicane for Briskoda trackdays

Dutch4x4

That would go a long way into explaining what actually happens.

But why?

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Mrs D's Briskoda: Octavia 4x4 turbo (2003), Oettinger 210, Koni Sport, MAD Sportive, Dotz Le Mans 17", Bridgestone Potenza S-03, sports interior. And a Fiesta ST (2006) for myself...

DGW

Perhaps because the electronic throttle is programmed for progressive movement, rather than the on/off action of flooring the accelerator pedal. For drivers who want to be so heavy footed, a simple on/off switch would suffice rather than using a pedal. In aircraft with FBW control systems, if applying full control movement resulted in immediate full deflection of the selected control surface, the aircraft would break. And with jet engines, if full throttle resulted in the immediate delivery of max fuel flow, the engine would overfuel and could flame out.

What I am saying is that if the ECU is programmed correctly, progressive application of throttle should give a better response (and performance) than flooring it, and I would be disappointed if it did otherwise..

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Denis

2002 Octavia 1.8T 4X4 turbo Estate - rebreathed on by Jabba ... 31.93mpg
2007 Fabia vRS - CC, ESP and full leather trim by Seat Surgeons ...48.57 mpg...

Dutch4x4

Hmm, seems reasonable, Denis. So it's the electronics saying to the driver, "Hey, don't do that silly stuff to me, or you'll kill us both!"

Oh well, doesn't hurt me much - I'm a progressive pedaller anyway, also on the brakes, for that matter.

An on/off switch? You mean like on a bumper car? Or what Jon's RS will feel like once the dustbin-sized turbo is fully operational...

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Mrs D's Briskoda: Octavia 4x4 turbo (2003), Oettinger 210, Koni Sport, MAD Sportive, Dotz Le Mans 17", Bridgestone Potenza S-03, sports interior. And a Fiesta ST (2006) for myself...

KLB

That makes sense - sort of

I've noticed a similar sort of phenomenon when taking my foot completely off the accelerator pedal at high revs (not something I do deliberately - just when I'm not planning far enough ahead, and have to lose speed faster than I intended).
Engine revs stay high for a few seconds, even though the car is slowing down appreciably. Presumably the ECU and Transmission Control Module (TCM) are discussing the best way to deal with the instructions from the human at the controls...

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Mike

Mircea

Denis,

This in not exactly what I am talking about.... Perhaps I get the meaning of flooring wrong, in my opinion it means to get the accelerator pedal at the maximum and it has nothing to do with how fast you do that... please correct me if am I am wrong

I agree that the ECU should filter stupid driver actions, and open the throttle in a progressive manner, but it should fully open finally and the boost should get at maximum level… It seems that this is not happening…

I do not see any ECU intelligence in the fact that the car pulls harder when you apply about 80% of maximum throttle or even when you reduce the throttle (slowly, it still happens) ….

Mircea.