Reduce throttle lag on Bosch Me7 Cars

[kujiwara]

Alright guys, my cars has a wierd custom tune from the PO, and the throttle response is no better than stock, so I googled and came up with this gem. http://forums.audiworld.com/showthread.php?t=2380969

I'm not trying lol anyone or anything right now although I made you guys think I'm a loller.
This is serious stuff. You might not have to pay $200 for a sprint booster if this works!
You're car's key must be turned to ACC position. And turn off to save each step during the tuning.
So, if you don't want to read the link.
1. Download unisettings from unitronic. And VCDS from Ross tech
2. Clear all codes on VCDS, so that your improperly maintained car doesn't break down during the test runs and blame be for being a scam.
3. Connect your car to unisettings, save the stock file on top right corner. Reload it if you don't like the new settings.
4. Set channel 1, throttle offset to -20 to begin with, from the link and my experience, the lower the number the more response you'll get, decrease by 10 or 20 each time to be safe.
5. Save the new file to your computer and name it whatever you set it to.

To test the setting go to third or forth gear at around 2-3k rpm, off throttle then step about 20-40%, hear and feel how fast the car reacts.

My car is set to -70 which I experienced quite a improvement, basically press-go, before was press----go. My buddy who have a 1.8T is set at -40 on stock tune said it improved quite a bit too.

Not sure if it will work on cars with tunes already considering the response may already be improved.

Tell me how much it improved or sucked in terms of: before press-----go, after-----go.

PS: I've heard rumors that unisettings don't work with HEX or whatever you call it the expensive OBD2 cables. However my $30 ebay cable worked great.

[kujiwara]

Re: Reduce throttle lag on Bosch Me7 Cars

And to show that I'm no scammer, if you drive a A4 like the one in the link or a MK4 and don't have a cable, I will do it for free for you during this month's Sunday coffee meet!

[MechEngg]

Re: Reduce throttle lag on Bosch Me7 Cars

Finally some good information.

Are you sure that this value stays unchanged however? I thought one of the functions of our ECU was that it learned your typical pedal movements and set this value specifically for your driving style. I am definitely going to look into this more when i get home today. Keep track of this number and report back in say a week and see if this value has changed at all.

[onceover]

Re: Reduce throttle lag on Bosch Me7 Cars

You should be able to do this through lemmiwinks too. Not sure why changing the idle offset would change the throttle response though, anyone have reasoning behind this? Theoretically this will also drop your idle RPM

edit: Sean, this value should never change unless you do it youself, its just an idle RPM offset...

[witchcraftz]

Re: Reduce throttle lag on Bosch Me7 Cars

Great information, thanks for sharing!

[kujiwara]

Re: Reduce throttle lag on Bosch Me7 Cars

Finally some good information.

Are you sure that this value stays unchanged however? I thought one of the functions of our ECU was that it learned your typical pedal movements and set this value specifically for your driving style. I am definitely going to look into this more when i get home today. Keep track of this number and report back in say a week and see if this value has changed at all.

I'm pretty sure MKIV ecu aren't smart enough to learn our driving style. At least not even the European B6 passat and 2006 Audi A4s. Looking forward to the results!

[kujiwara]

Re: Reduce throttle lag on Bosch Me7 Cars

You should be able to do this through lemmiwinks too. Not sure why changing the idle offset would change the throttle response though, anyone have reasoning behind this? Theoretically this will also drop your idle RPM

edit: Sean, this value should never change unless you do it youself, its just an idle RPM offset...

I'm not sure why it improves the response, but the idle rpm isn't actually changed.

[MechEngg]

Re: Reduce throttle lag on Bosch Me7 Cars

I'm pretty sure MKIV ecu aren't smart enough to learn our driving style. At least not even the European B6 passat and 2006 Audi A4s. Looking forward to the results!

Hmm i would beg to differ. Every single link i have searched through has said that our ECU's adapt to our driving styles. For instance if you are generally a more gentle driver, the throttle position maps shift so that it doesn't feel as fast as someone who drives around spiritedly all the time if you press on the pedal say 60%. Essentially it changes the ranges of your pedal. 50% throttle on my gas pedal (physically) could mean 40% signal to the throttlebody, where as on yours 50% could mean 50%. This means that if we push down at the same time and the same speed, yours will get a larger signal faster, making it respond faster.
You can easily do a TBA by taking off the negative terminal of your battery for a while and it will reset it to factory settings, which may increase your throttle response over what it was previously if you are typically a cautious driver.

Again if you can find some hard evidence (that thread is wishy washy at very best) that this works to prove me wrong i would love to hear about it, however i think you may have just reset your throttlebody and don't exactly know it.

[kujiwara]

Re: Reduce throttle lag on Bosch Me7 Cars

Hmm i would beg to differ. Every single link i have searched through has said that our ECU's adapt to our driving styles. For instance if you are generally a more gentle driver, the throttle position maps shift so that it doesn't feel as fast as someone who drives around spiritedly all the time if you press on the pedal say 60%. Essentially it changes the ranges of your pedal. 50% throttle on my gas pedal (physically) could mean 40% signal to the throttlebody, where as on yours 50% could mean 50%. This means that if we push down at the same time and the same speed, yours will get a larger signal faster, making it respond faster.
You can easily do a TBA by taking off the negative terminal of your battery for a while and it will reset it to factory settings, which may increase your throttle response over what it was previously if you are typically a cautious driver.

Again if you can find some hard evidence (that thread is wishy washy at very best) that this works to prove me wrong i would love to hear about it, however i think you may have just reset your throttlebody and don't exactly know it.

Ah, I didn't do any research on the learning stuff so you're most likely right on this one. I guess it's that my family drive our cars fairly cautiously then. Maybe with different Mk4s, see the throttle position and sensed position on VCDS could tell us the truth, we could do this in summer.

[kujiwara]

Re: Reduce throttle lag on Bosch Me7 Cars

An idle speed adjusting system for effecting feedback control of the idle speed of an internal combustion engine comprises a reference control amount output circuit for producing and delivering a reference control signal necessary for maintaining a command engine speed; a speed controller for generating a speed correction signal representing the offset of the running speed of the engine from the command engine speed; a flow rate controller for controlling the flow rate of intake air supplied to the engine, in accordance with the reference control signal and the speed correction signal; and an auxiliary flow rate controller for controlling the flow rate of the intake air in accordance with the speed correction signal and independently of the flow rate controller, so as to adjust the speed correction signal to a predetermined value. In the system, there is provided an ambient air temperature sensor for delivering an ambient air temperature signal to the reference control amount output circuit so as to vary the reference control signal in accordance with a change in the ambient air temperature. http://www.freepatentsonline.com/5024196.html

So what i read is that the ecu tries to correct the offset speed, but somehow for the Audi dudes and me that correction gave us better throttle response? May be overcorrection to the throttle position? I believe the ecu senses less revs then adjusts(increase) the throttle position to overcome the lack of engine speed, then the throttle position might be sensed at 7% while it's actual pedal is only at 2%? Therefore the throttle became more sensitive?

The idle speed didn't change because the ecu would modify the throttle signals when the actual pedal is at 0%?