cold idle fluctuating
6/6/14, 06:47 PM
#1
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cold idle fluctuating
happens on cold start just jumps up and down for a couple of secs the second i drive the car it goes away. Smooth as butter and no codes and I did an idle relearn a couple of hundreds miles ago but forgot to drive the car. Its kinda odd and if i dont touch the throttle on a cold start up and let it sit its fine. Its just when i start its and pull it out right away she doesnt like it any ideas. Bama hmmmmmmmmmmmmmmmm
6/7/14, 07:15 AM
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6/7/14, 11:33 AM
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Just took my car to the dealer to fix a rattle, fix the drivers window (rolls itself back down as it's going up sometimes), and asked them to look into fixing the warm up surge. The only thing they said they could duplicate and fix was the rattle and that took them 3 days. The window makes a tick sound while going up every time. I am assuming that is related to the times it catches and rolls itself back down but they didn't pull the panel to investigate. On the surge they said no codes, no problem.
They said the rattle was a loose RF brake backing plate. That seems to be gone.
6/8/14, 04:28 PM
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I was wondering about this behavior, as my car has it too. I thought it's something with electronic throttle control, but glad to hear it's pretty common. I just let it warm up a few more minutes on a cold day, and make sure to give it 1 or 2 gentle revs up to ~1500 rpm in neutral before I get going. This seems to make the driveoff more smooth.
6/8/14, 11:30 PM
#10
It's just the ECU learning. Every time you start the car after sitting, the weather is different and the ECU needs to set the parameters that make the car run most efficiently. You'll see it after loading a new tune as well. The first time you start the car, it may stall or run super rough for a few seconds until the ECU gets everything in order. It's nothing to worry about.
6/9/14, 08:48 AM
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Probably just due to the car being in open loop mode. It doesn't calculate the air/fuel mixture as accurately while the car is warming up and should run a bit on the rich side. http://www.thirdgen.org/open-loop-closed-loop
6/9/14, 11:45 AM
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Probably just due to the car being in open loop mode. It doesn't calculate the air/fuel mixture as accurately while the car is warming up and should run a bit on the rich side. http://www.thirdgen.org/open-loop-closed-loop
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