Q: My Toyota Sometimes dies when I break or press the gas very slowly

Common causes of engine stalling and rough idle include a faulty mass airflow sensor, faulty engine coolant temperature switch/sensor (typically at cold start only), worn spark plugs, wires or defective ignition coil(s), inadequate fuel delivery or pressure (clogged fuel filter, injectors), contaminated or old gasoline, defective throttle position sensor, faulty idle air control valve, leaks in the EGR system, intake vacuum leaks, and so forth. If you request an engine stalling/rough idle diagnostic the responding certified mechanic will get this resolved for you promptly. The fact that your check engine light came on during this incident will aid the diagnostic. The mechanic from YourMechanic would retrieve all the diagnostic trouble code(s) from your car’s PCM that have caused the check engine light to illuminate. Using those codes, the appropriate individual vehicle components or sub-systems (often a sensor, circuit, and the like) can be tested to pinpoint the cause of the fault or the reason why the check engine light has illuminated. Once the faulty part or component is identified, it is explained to your satisfaction and the mechanic will let you know of the cost to repair. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

You should have your computer scanned for codes first and then check the engine for any vacuum leaks and repair as needed. If no vacuum leaks then you may need to replace the idle control valve and verify the engine runs better. If still running bad then you may need to replace the MAP sensor and clear codes. If your first test shows that you have codes then follow the pinpoint tests for the codes and replace the bad components as needed after tests.