IAC on turbo v8 Help needed

[vp304]

I know lol nearly there just gotta sort out this tps problem. Any reason why i cant get it any lower tho?

[vp304]

Just started the car this morning stone cold. Still idiling like crap at around 500rpm hooked up to tuner pro dash and iac is at 196 steps.
tried shaking the cables and plugs for iac tps and map made no diffrence checking for crap connection.
Disconnected iac plug made no diffrence to idle

Might try original 1 bar map later once the car cools down and stock tune stock computer see what its like then
cause only things ive changed since converting it to turbo is the map sensor (its a genuine 2 bar) computer and memcal

[Holden202T]

have you tried crimping the IAC hose to see if it drops the idle at that cold time ?

[vp304]

not when cold only when warm ive tried it and it drops the idle by around 250 or so rpm. I screwed the idle up hoping the iac would close turn the car of and on rev it over 2000 rpm but it made no diffrence

[vp304]

ok car was cold
fitted 1 bar map and original computer tune still the same. Means i gotta look at the iac. its not computer related. 1 more thing im gonna try when its cold, is my gas converters get a feed straight out of the turbo outlet to help with mixtures whens its on boost. Im thinking disconect this line as it is forcing air past the iac, were as before na this didnt exist.

Tried the clamping of the iac hose when cold and it did drop the idle

[Holden202T]

well its hard to know if the iac is actually at 196 steps like it says, but its definately open if its effecting idle!

[vp304]

your right holden202 no way knowing how much it is open but its kinda like its open 2 much or not moving much or very slowly for some reason

started car up but was already at 60deg coolant temp
disconected the balance line before i started it made no difrence to iac and knoticed at idle it aint pushing any air so its not affecting it.

Ive managed to get the idle to about 750 rpm now and the iac to about 80 steps when warm.
What i knoticed tho was say when i put the headlights and air con on the iac would open up to about 130 -150 steps to lift the idle up (idle was still a little under 700 rpm) but when i turned them all off the idle would shoot up around 850 or so and would barley settle down. If i turned the car of and then back on again bang idle was perfect 750 rpm and iac at around 80 steps.

[VX L67 Getrag]

have you checked your mixtures?

If it's too lean or too rich either way it may beyond the IAC control system, but i'd still be trying to sort out the tps fault too!

[vp304]

Mixtures at idle are around .95 - 1 lambda and drop to .8 at full throtle. Once i do my clutch im going 10 psi spring in the waste gate and will richen up idle mixtures to low .9s at idle and cruise

[Holden202T]

i'm wondering if there is a fitting or some part of the pipe work that is too restrictive ..... so the IAC things its not open enough and just keeps opening cause it doesn't get the response it expects!