Having transmission problems in my 99 kia sophia.
It shifts funny and at 42 mph it shifts right to
overdrive and has no power and sometimes it
doesn't go into drive first thing in the morning. The
transmission was rebuilt 7,000 miles ago. The fluid
Try adding some Lucas Transmission Fix to transmission fluid helps hard shifting and slipping remove some fluid if necessary do not over fill.
They may not have built your transmission properly cause it sounds like your gears aren't shifting right, the car might be limp mode, to fix that disconnect your battery and rub the two cables together to reset your computer and then reconnect your battery and start it to see if it was in limp mode or not by acting the same way
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