You want to look at all your experience in the vein of hitting the job requirements for a PM, especially if you're changing from an engineer role.
What I recommend doing if you're changing roles is to read several postings for PM roles you might want.
See what skills/experiences come up again and again. Then take a hard look at your resume and think of how your previous positions hit those roles. Sometimes you have to rewrite the job experience to highlight the PM specific stuff.
In your case, I'd also mention somewhere in the cover letter or summary that you plan on sitting for the PMP as many jobs really really want that certification.
Project Management Professional® Certification (PMP) is a globally acknowledged professional certification program in project management, that legalizes a professional’s education and experience in project management.
It is known as the golden standard of Project Management and is acknowledged by organizations across the globe.
There's a youtube playlist that you can refer to in case you want to learn PMP and get certified.
Good luck!