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Intermittent soft 1-2 shifts at part-throttle

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Old 05-20-2009, 06:03 AM
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Default Intermittent soft 1-2 shifts at part-throttle

If the car is cold and I start driving it, the 1-2 shift is very harsh/firm, even though I am barely pressing the pedal.

Driving for about 20-30 minutes, I leave the car for about an hour. Start driving and the 1-2 shift seems softer than the 2-3 shift (at 1/3 throttle). However if I get on it, the trans never seems to let me down at WOT, nice firm 1-2 shift, screeching the tires almost every time. Eventually, part-throttle shifts start getting firmer.

Is this normal, or are my 1-2 clutch pacs going? I do have my shifts firmed up with Hypertech. Car has 26100 miles, last fluid change was at 22900 miles.
Old 05-20-2009, 09:06 AM
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Could be a PCS issue but could also be a tuning issue, There are different tables for cold and warm.
I doubt theres a 2-4 band issue since the shifts are solid at WOT in either condition
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Old 05-20-2009, 08:50 PM
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Not sure if it was coincidence, but I decided to "reinstall" the Hypertech with the same options I originally chose. Took the car for another ride somewhere and the tranny was shifting much better. The 1-2 shifts were still harsh when cold, but at operating temps the tranny 1-2 shifts were just as crisp as the 2-3 shifts. Seemed much more consistent in various throttle positions (1-2 and 2-3 feeling the same), and I was not able to replicate the "soft shift" issues yet.

EDIT -- Thought I would mention I don't have any codes going on (no SES light, and recently passed state inspection)

Last edited by Jeff 97 Formula; 05-20-2009 at 08:55 PM.




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