2001 Ford Explorer idles rough when at a stop in drive. Runs fine and idles in park fine. Surges also. Has new spark plugs and wires. Any suggestions of what may be causing the problem?

Sounds like a vacuum intake leak..check a those little tubes for cracks and security. also check your transmission levels, this will sometimes cause a surging problem while driving..if all this checks good then it might be dirty or clogged injectors..purchase a can of Sea Foam from Autozone $10 pour in 1/2 can to half tank of gas and drive around for thirty minutes..highway driving preferred, and see if that will clean up the fuel system.Can i get some feedback, thanks