What other engine works in 2002 explorer

For your year a 4.6 engine was an option. The 4.6 V8 2-valve engine had spark plug blow out problems. Caused by head design and two-piece spark plug construction. The 3 valve engine does not appear to have this problem. At a minimum you will also need a PCM re- flash, hopefully. It's definitely not a plug and play operation. Leave this one up to a professional. My 2004 F-150 came with a 3 valve engine and haven't had any spark plug problems and I have changed them twice.