Would you rather say....
Could you help me fixing the car?
Could you help me fix the car?
Could you help me to fix the car?

Question

Answer

"Could you help me fix the car please?"

I assume the context of this is asking a friend?

If you mean you're taking the car to a Mechanic (i.e. someone who you're going to pay) you wouldn't ask them to "help" you fix the car. You would say "Can you fix the car for me?"

Answer

The second one is right because we say "(to) help someone DO something" therefore there is no gerund (-ing) or "(to) + infinitive" after "help", so it is "Could you help me fix the car please?"

Good luck ^_^

Answer

Could you help me fixing my car?

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