Elantra A/T 2nd to 3rd over revs

A problem i have noticed recently is that when my automatic trans shifts from 2nd to 3rd it seems to over rev before making the change and isn't smooth like all other gear changes.
About a month ago i had the pulse genrator changed as i was experiencing a shift down into 3rd (fail safe) from overdrive. This problem went gone away after the sensor was replaced ($200cdn part).
Any advice on possible cause to this and what may be needed to solve it?
I don't have any codes as i've not had it to the dealer yet and the light i have on right now refers to a purge valve needing to be replaced.
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There is a reprogram available for '01 and '02 Elantras with this condition.
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Thanks again hyundaitech!
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I've got this same problem on my '03. It seems to have just developed over the last few weeks. Would this reprogram apply as well?
Thanks.
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The reprogram I found doesn't apply to the '03. It should already have the updated software from the factory. You may have a more serious issue. You may wish to take it in and have it checked.
You could try disconnecting the battery and seeing if it goes away after the transmission computer relearns. I'd doubt it, but it may be easier than going to the dealer first. The downside of this is that it would erase any stored diagnostic info.
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