Q: Why is my car is real slow to accelerate?

asked by on November 07, 2016

Why is my car real slow to accelerate? It hesitates to accelerate when I hit the gas.

My car has 156200 miles.
My car has an automatic transmission.

This may be related to a few different things, such as low fuel pressure, dirty or faulty fuel injectors or potentially a dirty or failing mass air flow sensor.

Low fuel pressure can cause the injectors to not receive the proper amount of fuel to be supplied to the cylinders. This is regulated by the fuel pressure regulator. The mass air flow sensor is a unit in the intake system that monitors air intake as it is mixed with fuel prior to being injected into the motor.

When this fails, this can cause an imbalanced air/fuel load to be supplied to the motor which results in an over fueling or under fueling situation depending on the conditions. This can cause the hesitation or loss of power you describe. This can also cause the engine to struggle to idle for the same reason. If you would like to have this resolved, a certified professional from YourMechanic can come to your home or office to diagnose the acceleration problem.

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