Ferrer, the top seed, clawed his back after losing the first set to beat Germany's Benjamin Becker 3-6, 6-2, 6-4 after the veteran Lopez won a tense shootout with Australia's Nick Kyrgios 7-6(2), 7-6(5).
Ferrer, 32, has a 24-25 record in career finals and will be appearing in his fourth championship match this year, having already racked up titles in Qatar, Rio and Mexico, in January and February.
"Today I didn't serve so well, but the most important thing is I was good in my mind and I'm very focused," Ferrer said.
"Tomorrow my return and my first serve will be very important. Feliciano is playing very good the last couple of months. I need to play with my forehand and make him move."
News that makes sense
Your trusted source for staying up-to-date with the world around you. Get free daily news updates and analysis, straight to your inbox.
The 34-year-old Lopez, seeded second in Kuala Lumpur, fired 12 aces past Kyrgios, 14 years his junior, to advance to his second ATP final this year.
"Experience is always a good thing to have but today I think the match could have gone either way," Lopez said.
"If you play a tie-break against someone who’s such a good server as Nick you know it’s going to be tight."
Ferrer and Lopez, close friends and Davis Cup team mates, have played each other 14 times over the past decade with Ferrer leading 8-6 head-to-head, including their last five matches.
The last time Lopez beat Ferrer was at Shanghai in 2009.
(Reporting by Julian Linden in Singapore; editing by Amlan Chakraborty)
