Q: Once engine is warmed up (3-4miles) car stalls at intersections and won't stay running.

Hi there. The correct way to diagnose most mechanical problems like you are describing begins with a digital scanner inspection. This allows the mechanic to download any stored error codes and then pinpoint the source of the issue. Once codes of no error codes are found, they should complete a test drive to attempt and replicate the symptoms you are having. This typically gives them a better indication of what is wrong with the car. After, they will dig into the engine and inspect the suspected components in order to make a diagnosis. Unfortunately, most mechanic shops will skip a few of these steps and make an "educated guess" as to the source of your problem. I would recommend having one of our mobile mechanics come to your location to complete a car starts then stalls inspection; so they can get to the bottom line as to what’s causing your problems.