Q: Why is my car stalling when reaching operating temperature?

Hello. This is a common problem on this generation of Impala. Some solutions I have seen work with this problem are replacing the mass air flow sensor or crankshaft position sensor. The mass air flow sensor relays to the computer how much air is flowing into the intake system to allow for the proper air and fuel mixture. When this isn’t working properly, this can cause it to stall. The crankshaft position sensor is a small sensor located down toward the bottom of the motor near the crank that monitors the speed of the crankshaft and relays this info to the car’s computer to help control the timing of ignition and fuel injection.

Similarly, when this is not working correctly, it can cause errors in the computer and cause the motor to stall. One other item to check would be the ignition control module. This (working with other components) monitors the ignition process after gathering data from other sensors to tell the motor when to fire. When this is malfunctioning, this can also cause the motor to stall. To have the problem scoped out in person, I recommend having an expert from YourMechanic come to your home or office to diagnose the stalling issue and follow through with correct repairs.