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Snowwebs
09-11-2023, 12:03 AM
I keep seeing a blip on my IAC.
It goes to an "IAC rest in progress" and an" IRC reset request", the motor position shows a jump from like 80 to around 256 and at the same time the desired motor position goes from 80 to 0, then the motor position starts counting down and gets to around 5, then the desired position goes back to like 68 and then actual position counts back up to 68.
All stays normal for a while, but then anywhere between 5 seconds to 20 min the reset starts over again. Each time the whole process takes only a second or two, and almost always when my speed is at 30 mph, a few times it was somewhere between 29 and 32 mph, but never anywhere else. neither the map, throttle position or any other data seems to have a relation that I can find.
I've seen it do it many times before and never really paid much attention, untill recently it started setting the IAC fault code that seemed to be repaired when I replaced the IAC motor.
But, it still does the whole reset thing.

I'm wondering if anyone else has this, and what causes this to happen. I cant find any settings or info about it.

This is a 7427 computer runninging a 95 k2500 with a 496 stroker/4l80e, it was a $OE originally but now running a $31.

Thanks for any help or thoughts
Ken

MO LS Noobie
09-11-2023, 03:36 PM
This looks like the normal IAC reset that the computer commands in order to reset and learn the pintle position. I dealt with these back when they were new. Never graphed them with a lab scope, but had to reset them when replacing the idle air control motor. I would make sure that the ports are clean in your throttlebody, and make sure that you have the correct IAC, there are at least two different profiles of the pintle. After it relearns the home position you shouldn't even notice the reset when it occurs while driving. If you do there might be something wrong with the drivers in the computer itself, or the software has gotten corrupted.

Snowwebs
09-13-2023, 04:32 AM
Thank you so much
That is basically what I needed to know. I did go back and look at some older logs an it was doing it on those also, and wasn't setting the code. I can't tell when it does it so it must just be the computer calibrating things
Thanks so much :thumbsup: