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Too much IAC kills motor?

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Old Mar 26, 2012 | 07:12 PM
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Default Too much IAC kills motor?

Hey all.. I'm experiencing an issue with my car and I believe too much IAC count to be a preliminary answer to what is going on.

I am monitoring this with my Aeroforce gauges which reads from the OBD2 port. I do not have any tuning software.

What is happening is at idle at operating temp the car is seeing about 140-150 IAC. Under load around 1500 rpm I am seeing 200+. Even higher rpm and the numbers just keep going up. Whenever I give it full throttle and come off on decel the car dies every time. The battery is new, starter new, alternator new, all grounds and cables free of corrosion and a nice connection 99% sure. The car stumbles as well when I give 1/2+ throttle once in awhile. Plugs are NGK TR6, I haven't checked those yet but its not misfiring all the time.

I am running a 4" diameter aluminum pipe with a 10" cone air filter on the end and maf between the filter and pipe orifice. IAC motor is still stock and came with the throttle body so who knows how old it is.

Here's another thing.. I wrecked my car and swapped everything into a new chassis. I had not experienced the issue with the last car. Same tune same everything motor wise except the intake I have instead of the Chrs1313, FTP 98mm air lid, and K&N filter.

So can too much IAC count kill the motor for safety parameters or something? I do plan to get a fresh tune for my new intake etc as well.
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Old Mar 26, 2012 | 07:40 PM
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Some other info. TPS when car is on and blade closed is .58 WOT is 4.48. Car idles pretty decent has trouble sometimes though. I think the blade needs closing a litttle more possibly. Throttle body is Nick Williams 102 cable. No port work, no hole in blade.
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Old Mar 27, 2012 | 01:59 PM
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so nobody has an answer..
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Old Mar 27, 2012 | 03:18 PM
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Drive by cable? I think your iac is mainly for idle control, doesn't affect open throttle conditions. The problems sound like the tune is off to me.
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Old Mar 27, 2012 | 03:43 PM
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I haven't seen anything like this, but wonder what is
driving IAC up that way. Desired airflow? Seems like
when you're talking loaded & 1500RPM, IAC ought to
be driven by the throttle follower / cracker. Maybe
these are indexed by something that's messed up but
not normally noticed.
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Old Mar 27, 2012 | 04:16 PM
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Its dying because there is too much air and not enough fuel, right? Becuase the IAC is opening too far?

Mine does the opposite. My counts at idle are around 20-40, and every now and then it will suffocate a little at idle but hasn't died since I replaced the Opti. I have replaced the IAC but no change.

Is there a way to "command" or tune the IAC counts?
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Old Mar 27, 2012 | 04:27 PM
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Idk guys like I said this is just one thing I noticed that stood out to me on my Aeroforce gauges and I knew it was way above the normal range. All I know is whenever I go full throttle the motor shuts off. I still have the key to ON so I have accessories etc.

I wrecked my car back in January and swapped it over to this new chassis. Same motor, same harness, same PCM, same everything except body control harness electrically. The only change I made to the motor was this new intake. It places the maf about 17-18" away from the throttle body compared to 6-7" as before.

I really need to get HPTuners... I may or may not be able to make it to a friends house to do a log.
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Old Mar 27, 2012 | 04:30 PM
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I think I solved the stumbling issue I had but not confirmed yet. I have a 58x LS7 so I have the LPE 58x - 24x converter box and the power wire was connected to the coils by bullet terminals male and female and was intermittent so it probably lost signal here and there. So I got a butt connector on there for now and no issues with losing signal when I flick the wire back and forth etc. So hopefully that was the stumbling issue, felt like a misfire but only intermittent.
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Old Mar 27, 2012 | 04:36 PM
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I think that might have been the whole issue actually... whenever motor was under high load it would vibrate around and lose signal for a second and regain itself and after a few times it would lose it completely. Then my car wouldn't start for a few minutes and randomly it would fire up again. Makes sense to me.. I'll give it a go here in a little while to see if that's what the issue was.
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Old Mar 27, 2012 | 07:32 PM
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Well I think I solved the motor dying issue. Didn't stumble once or anything. Going to get a log on the car this weekend hopefully anyways to see how the tune is with the new intake.
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Old Mar 27, 2012 | 09:57 PM
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Congratulations on solving it!
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Old Mar 28, 2012 | 03:33 AM
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From: Turnin' Wrenches Infractions: 005
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When you change the intake tract in any way you should retune IMO....though I'm not saying that was causing all your issues.
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