Audi idle valve configuration

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Krists
MS/Extra Newbie
Posts: 6
Joined: Thu Oct 28, 2004 3:38 am
Location: Latvia

Audi idle valve configuration

Post by Krists »

Hello, I have MS'ed my Audi S4 20VT 5cyl with COP system. Last weekend we tested it with the MSNS-e 029Q firmware ... well , the car runs really bad @WOT with the hires code - twitches like in convulsions :lol: (I'll have to downgrade the firmware to non-hires code), BUT this is not the task I'm asking for :)
I'm very happy with the possibility of tuning the idle valve more precise thought it's far from perfect.
Reading the posts of Keithg was interesting and they made me try the first steps into tuning the BOSCH idle valve, so I let You guys take a look at my settings and see what's happening here from a view of theory :)
The need for s cold start-"foot step" is gone, so I'm happy with the cranking DC value ... well ... it should be a bit less because @ cranking RPM shoots around 1200RPM so I could tune it for a smaller value.
In 'wamup only' mode, idle oscillates before the engine has reached the 90C+, after that there is smooth idle (I have to make it around 980rpm,now it's ~1000rpm),
In Closed loop state - idle oscillates in warmup and very,very small oscillation (+/- 20RPM in 10sec intervals) in warmed state (90C+ ). But the main problem is , that in closed loop mode, when I drive the car and let down the throttle, valve doesn't seem to hold the idle rpm and goes down until the engine goes off (this isn't something You wish to happen in a traffic jam :) )- if I just accelerate the car at idle, everything seems fine.
Here are my settings and BOSCH valve pic the car uses (The last diggits differs from the VW part numbers - thought I don't know how much there's the difference):
Image
Image
Thanks in advance!
keithmac
Master MS/Extra'er
Posts: 658
Joined: Sun Jun 19, 2005 12:52 pm
Location: UK, York

Post by keithmac »

Idle activation adder should be around 400 (it`s the target idle + activation adder that determine when the idle valve opens), I find a Dashpot adder of 6 works quite well (this stops the car stalling when coming onto idle).

The code won`t be working properly at the momnent with such a high Idle Activation Adder..
Squirted VW GTI 16vG60 mk2
Krists
MS/Extra Newbie
Posts: 6
Joined: Thu Oct 28, 2004 3:38 am
Location: Latvia

Post by Krists »

Keithmac, I changed the things as You wrote - the IDLE now oscillates like CRAZY ... starting from 2000 to 3500 with 5sec intervals :shock: It was hot today and the coolant temp showed 95-98C. Thought my laptop died and I had no chance to play with idle values and I just plugged-off the valve because the car wasn't driveable :) I hope to change the code to 29Q2 w/o hires un try to tune the closed loop idle again!

Any thoughts why the idle was oscillating like crazy ?
2713ddddavid
MS/Extra Newbie
Posts: 9
Joined: Sat Apr 15, 2006 2:24 pm

Post by 2713ddddavid »

sorry to jack the thread but I have a question.

What is "target idle" when you speak of target idle and activation adder?
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