transmission shifts hard

2006 HYUNDAI SONATA
148,000 MILES • 3.3L • V6 • AUTOMATIC
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TRELISHIEAPRINCE
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My car shifts hard and rough out of gear and also accelerates on its own when I place it into gear.
Jul 1, 2017 at 9:50 AM
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STRAILER
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Hello,

It sounds like you may have a plugged catalytic converter which messes with the MAF. Here is a guide so you can run some tests

https://www.2carpros.com/articles/how-to-test-a-catalytic-converter

Please run some tests and get back to us we are interested to see what it is.

Cheers, Ken
Jul 3, 2017 at 1:03 PM