I failed the exam on my first attempted due to the same reason. However, I took a review course in nyc. And the first thing they made me do is to buy and tag Wilidi book. I would say at least 8 questions were directly from Wilidi book. So for theory problem ( motor, generator, VFD, electric...
First of all I recommend all PE exam taker to periodically visit engineerboards.com. The best PE Power classroom setting review course in NYC is from Saamce.com. For online review, schoolofpe is one of the best.
Good luck.