MembersPage/NanassyPeter/AirFeed (2006-02-27 04:04:27)

Now i will have a little time for upgrade the car.

I want to use a stock Audi Bosch Idle air valve,2 pin,cigerette style.

How to wire it?

And how to configure it in megatune?

idle air solenoid - wired

I "manually" opened it with 12V, it cliks, so it's functional! I also measured its impedance: 4.1 ohm.

Pin1 to Ignition Switched +12V

Pin2 to EC36-pin6

I tried to set to PWM as discribed, and i choose INJFET #7.

Configuring for Injector Driver #6 channel. See GenBoard/Manual/DigitalOut and GenBoard/Manual/DigitalOut/Table

I can measure 12V between Cylinder Head and "Pin1".

Progress

Ok , i set that h0 so it works now,but only in on/off IAC valve mode,it really pushes the engine from 900>>>to 1500 RPM.

PWM mode

I also tried different PWM freqvencies from 10-255,no luck.

Note,that i have taken special care of engine variables,set everethigh (temps,RPMs i mean) insane high,but with PWM its not working.ANY ideas?

My own answer

The Reference table was set to 1 (all CLTs) so the IAC valve was not able to produce me some RPM increase.

Now this rpoblem is solved,but i need some finetuning hints,and basically i want to understand how this feature works.

I want that with cold engine it starts like a champ,so i set the reference table

-40c to 90%

77c to 85%

i also want that the engine RPM below 40C set to 1200RPM,so

"Idle cold RPM" is 1200

Max temp. for cold idle speed is 40C

With warm engine 920RPM will do the job nicely

"Idle RPM warm engine" 920RPM

Min temp for warm RPM is 70C

See PIDControlTuning

What i notoced is that tough the warm engine RPM was set to 920 and the engine CLT was above 70C ,and TPS was below 3% the engine current RPM was 1050, BUT THE IAC STILL SHOWD 6-8%DC.

Too low iac_integral_limit_dec ("iac integral decrease limit") together with PID values especially I value) didn't allow the iac to deviate enough below the reference position (10% for the given temp, if I understand right. Your published config contradicts this: iac_ref_pos[9]=4D which is 30%, not 10%).

Btw, share the relevant part of your config when asking for advice.

Ok,sure i will share my config.The confusing part is caused by the manually closed throttle valve (it was opened too much for IACless operation!),so i had to give more reference position ,from10%>>>>30%,dont worry about it:).Tough the behaviour what i described is not affected by this,and the hints you gave me are very helpfull!

Do NOT duplicate questions, especially on the same page! Just touch the text or emphasize to call attention.


System description:

The Audi Inline 5 cyl. engines (all types) uses 2pin PWM solenoids,but the older ones (10valve) are much more restricted,so they flow less.I have a newer AAN engine but with the older IAC valve.Tough i think this wont alone cause any problem,i created another:).This valve has approx 20mm in and out connectors for air ,but unfortunately i had to reduce the hose from the IAC to Intake Manifold from diameter 20mm to diameter 8mm.

What i noticed during IAC tuning was that the valve dont have a smooth control range.There is of course a difference between 30 and 100%,but there are "blind" sections.This is explained maybe with the insane high freq i use (50) ( i tought it is real Hz),or maybe the resticted valve??

So first,i will set this to a reasonable 3..10 value,and start the whole tuning again.

Thanks for the instant support.