IS - 2nd Gen (2006-2013) Discussion about the 2006+ model IS models

IS 350 with jerky acceleration (from stop)

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Old 04-13-08, 06:34 PM
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sammy5001
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Default IS 350 with jerky acceleration (from stop)

Premise: I have a new 2008 IS 350 with 300 miles on it so far.

Problem: Thus far I find that the acceleration (from a stop) seems very jerky. I've tried applying various degrees of force on the pedal and it doesn't help much. In fact, the acceleration is the smoothest if I just floor the pedal. When I hit the pedal softly, it seems as if though the transmission shifts from 1 to 2 then to 3 too quickly and prematurely. If I turn on Power Mode, then it holds the gear longer and the acceleration is much smoother. But I don't want to keep it in Power Mode because I want to save gas. Anyone else having this this problem? With the default (non-Power and non-Snow) mode I'd expect the ride to be the smoothest--clearly that's not the case.
Old 04-13-08, 06:39 PM
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stvn
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i thought the upshifts were not as fluid as they could be at first too, but after riding for ~2500 miles now the shifts seem a lot smoother like the transmission evolved..? also you will eventually learn when the car shifts gears and you can vary your pressure accordingly
Old 04-13-08, 06:49 PM
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HKS350
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The ECU is in "learn mode" right now. Give it time and drive the car normal. If you are off and on the gas trying to get the car to stop the jerky feeling the ECU will learn this driving style.
Old 04-13-08, 08:00 PM
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iKenn
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is it in ECT PWR mode?
Old 04-13-08, 08:10 PM
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llamaboiz
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i run in snow mode
Old 04-13-08, 08:12 PM
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iKenn
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oh i should have read the whole post.
Old 04-13-08, 08:28 PM
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Zinda
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I am interested in this issue because I have different people driving my car. So does the ECU adjust for them as well?
Old 04-13-08, 09:41 PM
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eric_r_ho
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Bring it back to the dealer and have them re-adapt the transmission..maybe it wasn't done right from factory. Let the transmission learn the values correctly. It happens..
Old 04-13-08, 09:52 PM
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RTIS250
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The shifting should smooth up in time... my 250 shifted erratically at first also, and now i just over 1200 miles on it, and it seems to be a night and day difference. If you are really concerned, you can bring it to the dealer and have them reset the learned values, and it can start from scratch again. No such thing at "re-adapt".. I think you'll be ok though.
Old 04-13-08, 10:56 PM
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Rividsoul
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Hopefully this is not a dumb question, but does the MT's ECU have a learn mode as well?
Old 04-13-08, 11:02 PM
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eric_r_ho
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Originally Posted by Rividsoul
Hopefully this is not a dumb question, but does the MT's ECU have a learn mode as well?
I doubt it..if anything it just has a fuel trim compensation for the ever-changing/deteriorating condition of the motor..
Old 04-14-08, 09:37 AM
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crzyis
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****DO THIS AT YOUR OWN RISK!****

Just pull your EFI and ECT-S fuse in the box wait about 2 min put them back in and the tranny will be rest in learning mode. The first time you go to start the car it will not start but hit it again and it should come up just fine.


****DO THIS AT YOUR OWN RISK!****
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