When the engine misfires or have a faulty oxygen sensor, it typically creates a fault code and illuminates the check engine light.
Is you check engine light on?
If it is illuminated then scan for the trouble codes.
From what you are describing it sounds like the engine is misfiring under load as you go up a hill. Most common cause of misfire is faulty spark plugs.
You might want to do a basic tune up to restore the performance of the engine.
Here is helpful video of how to determine the faulty spark plug:
I have attached diagrams for your reference.
Please let me know of any questions.
Images (Click to enlarge)
Wednesday, August 18th, 2021 AT 7:56 PM