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Q: Hesitates and jerks

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When taking off if, there's any hill it hesitates and jerks. Once I get to 30 to 40 MPH, it stops for a minute. No smells. I did smell a gas smell today a little. If the car is in park, it idles fine for the most part.

My car has 76315 miles.
My car has an automatic transmission.

A: Hi there, thanks for writing in. I'd be...

Hi there, thanks for writing in. I'd be happy to help.

This is a common sign of a faulty mass airflow sensor or throttle position sensor.

The mass airflow sensor regulates the amount of air that is mixed with the fuel prior to it being injected into the motor. The throttle position sensor monitors the position of your foot on the pedal and relays this info to the computer which then directs the fuel injection system as to how much fuel to supply. When either of these is not working properly, this causes an imbalance in the air/fuel ratio being injected into the motor which is what causes the jerking and hesitating you describe.

If you would like help, consider having an expert automotive technician from YourMechanic come to your home or office to inspect and diagnose this issue for you, and make any repairs as needed. Hope this helps and best of luck!

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