Skip the auto shop - Our mechanics make house calls

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

asked by on

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.

A: A number of components or faults can cause ...

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.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Car idles low. What's going on?

Hey there. The engine will need to be checked for vacuum leaks in the PCV system or if the Check Engine Light is on and the idle control valve stopped working. Have a mechanic scan the computer and test the...

Q: My car's engine runs rough at idle - 2001 Chrysler Voyager

Hi there. From what you've described/shown, it seems that the mechanic put the timing belt back on one tooth off. If all of a sudden the engine is not running correctly and the vacuum has dropped, then a valve is...

Q: Truck stalls when stopping ocassionally. 2001 Mazda B4000

Hello. There could be a problem with the throttle position sensor or the idle air control valve. Both of these sensors help control proper air-fuel mixture and engine idle. Sometimes carbon builds up and clogs the idle air control valve...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
What are the Car Pool Rules in Hawaii?
Hawaii is widely regarded as a land of vacation and relaxation, and as such, its scenic roads and routes are far better known than the state’s freeways. But, as with all...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.