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Gm/Holden 4 wire stepper iac issues


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Hey guys finally getting to tuning this turbo 304 on g4+ storm and the Iac is not working as expected.

At first it was happily clicking away at key on resetting itself but would always idle high upto 1500rpm it occasionally works and drops idle to target of 750rpm .

then it would hang after a rev and take ages to drop if it dropped at all and now it doesn't even move when I key on .if I take it out of the throttlebody it just gives a brief hum at key on no longer makes any noise resetting itself.

I can plug the Iac into my daily with factory Holden Delco ecu and it works fine its just like the link isn't supplying enough current to drive the stepper

Have also tried a second iac with the same results

It's wired as per instruction to aux 5 6 7 and 8

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Thanks for the reply Simon 

So updated to the latest  pclink software and flashed in the new firmware

iac is sort of working lol the ecu is loosing track of where the Iac is.i got it to idle at target rpm then I tap the gas and it goes to 1600rpm and stays there for around 1.30 minutes then slowly over a minute comes back down to target rev it again and it stays high forever adjust max clamp till it comes back down and give it another stab and it locks high again adjust clamp well past the maximum amount of steps possible for a gm Iac and it comes down again but yet again as soon as I touch the gas it holds revs bad it's just a constant battle of it loosing losing its position .even after keying off and restarting it can't sort itself out 


The other thing is every update tge software is getting slower and slower the software is now so slow in win10 that I would nearly call it unusable the last version was ok after it started and sorted its shit out this version its slow selecting any menus takes ages going from one setting to the next as it is a long wait for anything to happen

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For the loosing track of the position it might be that it is hitting the end of its travel during reset. Also if the base step position is to far out on throttle blip it can hang high. 

On the software it seems to be related to the graphical view of the tables. If you se the layout up with no graphical views open it should be much faster. 

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