95 jetta need expert help

My wife has a 95 jetta III. we just recently bought. i am getting ready to PCS to korea and dont have a lot of time nor do i want to leave her here in NC in the heat with no car. Its a 95 Jetta III with a 2.0 its a automatic and has a mexico engine. We have put the car in the shop with no results. when it is warmer then 70 outside the car will spit and sputter. its not bad at idle but during acceleration it will spit and the hotter outside the worse and more often it will do it. Sometimes i have to put the gas pedal all the way down for it to pull out of it. the temp light was coming on so i changed the thermostat. It solved the light problem i also noticed the water pump has a small leak. so small that the antifreeze only dropped a 1/8 inch in 2000 miles but there was a little evidence of a leak. i dont know if this would cause my problem. but i dont think it is the culprit. The temp gauge dosnt seem to really move more the ordinary. the car drives completly fine in winter or on cold days. but it starts acting up as it warms up. any help would be greatly appreciated. thanks

Did you check the distrubutor cap sometimes that gets curotted(sp)