Richard Cresswell had headed Preston in front before Jody Craddock equalised with his first of the season.
Graham Alexander put Preston ahead again from the penalty spot after Jolean Lescott had fouled Lewis before Seol's equaliser from 18 yards out.
Wolves boss Glenn Hoddle:
"I wasn't pleased with the way we played first half. I thought we gave the ball away too often.
"We won it off them on numerous occasions and gave it straight back, which we haven't been doing.
"There were a few stern words said at half-time, which were needed and I was pleased with the way we responded."
Preston: Day, Alexander, Mawene, Lucketti, Davidson, Sedgwick, O'Neil (Etuhu 81), McKenna (Davis 90), Lewis (Agyemang 82), Cresswell, Nugent.
Subs Not Used: Ward, Mears.
Goals: Cresswell 3, Alexander 53 pen.
Wolverhampton: Oakes, Edwards, Craddock, Lescott, Naylor (Cooper 71), Olofinjana, Ince, Kennedy, Seol, Cort, Miller (Clarke 89).
Subs Not Used: Cameron, Jones, Andrews.
Booked: Naylor, Miller, Ince.
Goals: Craddock 10, Seol 73.
Ref: A Mariner (Coventry).