I have this issue tht just started happening with my geo. When its in park and nuetral it idles fine but when I put it in drive it kind of sputters like it has bad gas or something. And same thing when im at red light. But one I get up to 20 plus miles an hour it runs fine no noticeable sputter until I come to a stop. Even tho its an older car the check engine light does work and is not on, and it has been fully tuned up with new alternator, spark plugs, distributer cap and button, wires, and new belts etc. Oil levels and transmission fluid are good as well so im kinda stumped what could be causing this any ideas?