Question

I just wanted to know if number 2 is completely wrong.

1.I havent' finished repairing the car enginge.
2.I haven't finished to repair the car engine.

Thank you.

Answer 1

Neither is correct, although I know what you're getting at. Here's the correct sentence:

I haven't finished repairing the car engine.

#2 is not correct because we don't use an infinitive after "finish(ed)" -- we use a gerund.