It sounds like the engine is in limp mode because of a computer issue. Lets start by running the codes to see what come up so we can go from there to fix the car. Here is a guide that will help you:
Did the diagnostics and the code P2128 and P0435 came up.
Oct 14, 2018 at 1:55 PM
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The code P2128 is telling us you have a problem with the throttle actuator. I would try cleaning it first. Here is a guide. Disconnect the battery before you begin and clear the codes once completed.
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