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Resetting ECM loose Flash

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Old Nov 11, 2006 | 12:16 PM
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Default Resetting ECM loose Flash

Hey guys I have been thinking about resetting my ECM because of an Idle problem I have been having. The questions is I used to have an A4 in my car and I swapped it over to a 6speed and had the ECM flashed to stock m6 tune. If I reset the ECM will I loose this flash and have to go get it flashed again? The reason I ask is because I swapped out my IAC valve today and when the car is cold and I start it it will immediatly rev to like 3 grand and won't come back down. If I take the IAC out and put it back in the car will start normal and idle right at 800. If I turn the car off and then start it back up it will go right to 3k again but come down in a few seconds. My old IAC doesn't do this. Is this a ECM related issue or not. I threw a cam sensor code a while ago but it went away and has been running fine ever since.
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Old Nov 11, 2006 | 06:01 PM
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Resetting the PCM resets fuel trims and IAC count but does not change flash memory.

Last edited by Gary Z; Nov 11, 2006 at 06:12 PM.
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Old Nov 11, 2006 | 07:35 PM
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flash means to rewrite.when you flashed the ecu your factory tune was erased complety.then the new tune was wrote.
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Old Nov 11, 2006 | 08:57 PM
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Sounds good. I have a new IAC that I bought from autozone and the damned thing just is not working right. If the car is cold it will fire up to 3K and stay there. If I pull the IAC out and mess around with it then it will start normally and idle fine. But when I drive when I go to push the clutch in the revs will keep going up like I am still pressing on the gas. The old one will not do this and it will work just fine except for the bouncing rpm ****. The plunger looks a little different on the new part could it be the wrong part? Mods feel free to move this if possible I just thought I would get a better response here.
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Old Nov 11, 2006 | 10:44 PM
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Your Idle Air tables need to be customized for your mods/vehicle. Pulling power resets the idle learning but, evidently you have a issue that needs to be corrected.
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Old Nov 12, 2006 | 10:03 AM
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I can put the old IAC in the car and it starts up fine everytime. It only does this weird crap when I use the new IAC. This tells me either the IAC is the wrong one or something. The connector does fit in it rather loose. Does anyone know if you need to adjust these things. I noticed on the IAC valve I got you can screw it in or out for adjustments it doesn't get tight unless you bottom it out. Do I need to work on adjusting it maybe?
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Old Nov 12, 2006 | 10:53 AM
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put in the new IAC, leave it unplugged ,unplug the TPS ,turn the key on wait 30 second turn it off for fifteen secs, repeat, plug them both back in erase the codes this should reset it all
Log IAC counts and look for a vacum leak

Good Luck!
Brent
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Old Nov 12, 2006 | 11:10 AM
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The adjustments are in the calibration tables. Like Brent said, other than doing a key on unplugged electrical zero reset you need to monitor it with a scanner. I would'nt "try physically" adjusting it too much or you might strip out the gears.
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what is iac
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Old Oct 17, 2017 | 10:40 AM
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Idle Air Control
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Old Oct 18, 2017 | 07:04 AM
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"The connector does fit in it rather loose. Does anyone know if you need to adjust these things. I noticed on the IAC valve I got you can screw it in or out for adjustments it doesn't get tight unless you bottom it out."

Wrong part.
1. It's not supposed to be "adjustable".
2. If the plug fits loose, it's a sure way to get a FUBAR connection.
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Old Oct 19, 2017 | 11:03 AM
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I would say your new IAC is bad if the old works fine. Why not just use the old one. Doesn't sound like a PCM issue it seems like an Autozone sensor problem.
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