* Vacuum leak
* Dirty throttle body
* Faulty idle air control valve
* Faulty oxygen sensor
* Failing fuel pump/fuel pressure regulator
* Low refrigerant level (on vehicles with A/C)
Stalling While in Gear:
* Low transmission fluid level
* Dirty fluid/faulty transmission solenoid
* Faulty throttle position sensor
* Faulty camshaft position sensor
* Failing ignition coil(s)
* Faulty fuel injector(s)
It is recommended to start troubleshooting with checking fluids for proper levels and/or contamination first, followed by cleaning or testing suspect components and sensors to address faults as necessary.
