Yes.

Student or Learner
Is the word "engine" countable? For example, "My new car has a powerful engine."
Yes.
I'm not a teacher. I speak American English. I've tutored writing at the University of Southern Maine and have done a good deal of copy editing and writing, occasionally for publication.
Why do you think it might be uncountable?
Wouldn't two new cars have two engines?
I'm not a teacher. I speak American English. I've tutored writing at the University of Southern Maine and have done a good deal of copy editing and writing, occasionally for publication.
Look up any noun in a decent dictionary and it will tell you if it's countable, uncountable, or both.
Remember - if you don't use correct capitalisation, punctuation and spacing, anything you write will be incorrect.