I am a pretty devout zippo user, and have never found that gas like taste come through my pipe when I figured it all out. Try holding the pipe insert zippo a little above the rim of your pipe, that will help. Also, the black can of fluid is helpful as well. The last tip I can give is to let the wick burn for a bit, I find every time I pull up more wick I get the taste again. When the wick is good and black it goes away.
Hang with it and the zippo will reward you. It never goes out, always lights easy, and with it's warranty it will outlive you. I picked up an old beat up brass one at a second hand shop for about 5 bucks today and after a new flint and some new fluid it lit like a dream. I'm going to send it off to have a pipe insert put into it so I can keep a backup in my car :D