Q&A

 Master

The idle speed is electronically controlled so I would do testing of that circuit and component. I would look at the air fuel trim values on a scan tool to see if there is a vacuum leak (if so the fuel trim figures would reflect "adding gas". Test things as opposed to replacing things! Autozone have some popular workshop manuals for free on line once you register (for free) on their website http://bit.ly/autozone_repair_info.
and get an online repair manual subscription. There is a company that independent auto repair shops "buy" their information from that the same information inexpensively to do it yourselfers. The information is year make and model specific repair procedures, service bulletins, component locations, wiring diagrams ect.... Alldata is very easy to navigate http://bit.ly/AllData_Repair_Manuals_Online

 Master

Check for a vacuum leak or an air intake leak. Other than that, would have to monitor for spark and fuel when the failure occurs.

 Master

Intermittent engine stalling when taking foot off accelerator pedal (coasting) or coming to a stop is frequently caused by a dirty Throttle Body. The throttle plate and bore may become coated with contaminates from the intake system. This restricts the amount of air flow past the throttle plates at closed throttle to allow the Idle Air Control motor (IAC) to compensate and keep the engine at it’s programmed target idle. If the throttle body plate and bore are coated with contaminates. On some engines, removal of the throttle body is not necessary to clean.