I just got my Mazda 626 repaired after about 2 years of sitting idle. After we first got it it ran like a charm. But then after a while I noticed the car starting to shake while stopped in drive. Eventually it got worse until one time while stopped at a red light the car stalled completely. It now continues to do this on queue almost anytime the car is stopped or idling in drive. The mechanic we went to mentioned something about moisture on the gas tank. Could this be it and what is the remedy? If not, does anyone have a clue? Thanx!

The mechanic is most likely right. The behavior you described sounds like water in the gas. Buy a bottle of dry gas (like a buck) and pour in with a full tank of gas. You should see results after driving the car for an hour or so.

If that doesn't clear it up, then you may have some timing problems which will cost a whole lot more then a buck to get fixed.

You could also have a problem with carbon in the idle air control valve...You can take it out for inspection and cleaning.