Q: My car runs rough at idle, stalls at idle, surges, and idles at 40 miles an hour

asked by on October 31, 2016

What do I need to replace to stop rough idling, stalling ,fast idling (40mps) and surging. Already replaced throttle body sensor.

My car has 75000 miles.
My car has an automatic transmission.

Car is stalling Inspection $94.99 - $114.99 Get a Quote

A number of components or faults can cause your issues. A vacuum leak can cause your issues. Depending on the vehicle, components such as the mass airflow sensor, throttle position sensor, coolant temperature sensor, and a number of others can be the cause. Since randomly replacing parts can get expensive as most electronic components are not returnable once installed, having a certified technician, such as one from YourMechanic, diagnose the stalling/surging is the best place to start.

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