seems to skip 4th gear, and check engine light comes on..
while driving 2005 optima lx seems to skip 4th and have some loss of power and check engine light comes on.
Try to have the codes read when the check engine light is on from this issue, the computer system in that car might have the transmission computer linked together (if not a dealer can read transmission codes) so you may be able to find out what exactly is happening from what the code says.
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