Q: Car stalling when driving.

There are a couple of things that come to mind with this particular issue. The first thing to do to start diagnosis would be to read out the faults from the engine computer and begin by correcting those issues first. If no faults are present another thing to look at would be the idle air control valve. If the idle air control valve is sticking shut it may be possible that upon deceleration that the valve is not opening back up to resume idle when stopping or parking. Another thing that is a known issue on the Freestars is moisture entering the plug of the engine computer. This moisture will short out inputs and outputs from the engine computer causing malfunction, rough running issues, etc. The cowling will need to be removed as the engine computer is located just under the bottom right corner of the windshield. The engine computer plug can be removed once the negative battery terminal is disconnected. The plug is then dried of moisture and then sealed with dielectric grease to keep moisture out of the contacts. You may want to enlist the help of a mechanic, such as one from YourMechanic, who has the training and diagnostic equipment to assist in this diagnosis and repair.