Idle adjustment on TDi 05

[Sage]

Hi all,

I know these cars are fly by wire though i am curious if the butterfly can still be adjusted to raise the idle by 100rpm or so?

I did do a search though people were talking about VAG COM and the like. I am old fashioned and i'm curious if i can just adjust the butterfly or something similiar?

Thanks for your help.

[Greg Roles]

Fraid not. The ' butterfly' in a tdi is purely an emissions and engine shutoff item, and doesn't act as a throttle. It's designed to actually restrict the inlet before the egr addition and draw in exhaust for recycling. Unlike petrol cars, which throttle air inlet, diesels throttle fuel, and would run just fine without any inlet 'butterfly'. Only older mechanical injection diesels have screw adjustment, not that I have experience there.

[Sage]

thanks for the reply Greg. thats unfortunate. So in order to adjust the idle i need a ECU reflash i take it?

coming from a guy who generally has owned cars with carbies i cant imagine not being able to adjust idle by something physical..

[wokwn]

The MK4's could adjust the idle +/- 100RPM using VCDS. I don't think the same applies to the MKV's.

[Sage]

i am thinking about rigging up a new throttle pedal stop for it )

[manol]

Why do you want to do this?

[nutttr]

I believe that you can for the 2L TDI - Have a google search - It's locked in a setting under the engine settings - From memory the password you need is 12233 to access it, but I don't remember what group or setting it is that you need to change, but it will be marked. It's near a setting that has the value 65335 or similar! The idle RPM will be about 820-840 currently, I know you can turn it up, but it's advisable - unless the engine is stuttering - not to do it.