Engine surging when accelerating is most often caused by bad mass air flow sensor, bad throttle position sensor or fuel injection problems or bad spark plugs.
When your car's speed is not responding to how hard you press the gas pedal the problem can be bad spark plugs, bad ignition coils, bad timing belt, clogged air filter, clogged fuel filter, clogged or bad fuel injectors, low fuel pressure or bad fuel pump or a bad throttle position sensor.
When your car hesitates when accelerating without the check engine light the most common cause is a clogged fuel filter or low fuel pressure or dirty or clogged fuel injectors.
Bad spark plugs and clogged air filter or low fuel pressure can also cause a car to hesitate when accelerating.
A bad throttle position sensor can also lead to a car hesitating when accelerating with or without the check engine light as the throttle position sensor tells the computer how much fuel the engine needs depending on the position of the throttle.
To fix engine hesitation during acceleration you must first find out what is causing the engine hesitation while accelerating.
Common issues that can cause engine hesitation when accelerating are a faulty throttle position sensor, faulty mass air flow sensor, bad spark plugs or bad spark plug wires, clogged fuel line or clogged fuel filter, bad fuel pump, low fuel pressure, dirty air filter, bad or clogged fuel injectors, low engine compression.
Most common fixes for engine hesitation include replacing the fuel filter or the fuel pump.
You can test a throttle pedal position sensor or throttle position sensor by using a multimeter.
To test the throttle position sensor with a multimeter you set the multimeter to DC voltage and then you connect the red lead to the signal terminal of the throttle position sensor and then connect the black lead to the ground.
You should test the throttle position sensor when it's fully closed and when it's fully opened.
Generally you want to be between 0.2 and 1.5.
But some throttle position sensors read as low as 0.1. 3 so this is good.
The cars computer or ECU units control the throttle position sensor by electronic throttle control or drive by wire systems.
The throttle position sensor tells the computer where your throttle is positioned at and tells the computer to send either more fuel or less fuel to the engine.
The sensors that can cause a car to not accelerate are the throttle position sensor, mass airflow sensor and the oxygen sensor.
Other things that can cause a car to not accelerate are clogged or dirty air filter, clogged or dirty fuel filter, bad fuel pump, bad spark plugs, low fuel pressure, dirty or clogged fuel injectors, faulty fuel injectors, ignition timing issues, compression issues, timing belt issues.
Throttle position sensors do not go out very often and most throttle position sensors last the life of the car or other vehicle.
However some throttle position sensors may need to be replaced after 150,000 to 250,000 miles.
A throttle position sensor can last a long time and only need replaced when they go bad or test bad.
You do have to reset the computer after replacing the throttle position sensor by resetting the throttle position sensor itself which is pretty easy.
In some cases simply resetting your current throttle position sensor can fix most issues with the throttle position sensor.
To reset the throttle position sensor you first unhook the battery and then reattach the battery cables.
Then set the ignition to on and then push the gas pedal all the way down to the floor and then let it go.
After that turn the key to the off position and the throttle position sensor should be reset.
You can clean a throttle position sensor and sometimes that will help fix the throttle position sensor if it's just stuck.
Throttle body cleaner can be used to clean the throttle position sensor but don't use too much and be sure to remove grime or dirt on and around the throttle position sensor.
If the throttle position sensor is still not working then it will need to be replaced with a new one.
A bad throttle position sensor will lead to your engine running poorly and you may notice that you have poor acceleration.
With a bad throttle position sensor the computer is not telling the injectors to inject more fuel into the engine as you accelerate as the throttle position sensor works with the vehicles computer.
Common signs and symptoms of a bad throttle position sensor include.
Intermittently flashing of your check engine light for no other apparent reason.
Sudden surges in speed while driving down the highway.
Hesitation or sluggish engine when accelerating.
Sudden engine stalling and sudden idle surges.
And unexplained bucking and jerking in the vehicle.
A throttle position sensor will throw a code when it's bad or not operating properly.
The code for a bad throttle position sensor or TPS is a generic code of Po122.
When the TPS or Throttle Position Sensor goes bad the throttle body may not open and the engine will not be able to run without air.
A bad throttle position sensor or TPS may cause erratic idling, stalling, and sudden surges of acceleration.
The car may not start when the TPS is faulty.
Your car may idle or misfire when stopped.
You may also notice that your car accelerates itself, hesitates to accelerate, or come to a halt altogether.
You may also face difficulty changing gears and experience other issues with the car's air conditioning, ignition timing (ignition system), or fuel efficiency.
A bad or failing throttle position sensor can cause problems such as hard starting, rough idling, loss of engine power, increased fuel consumption, loss of engine power upon accelerating, slow idle, and failure to start as well as check engine light to come on.
A properly working throttle position sensor is essential to a properly running engine and to keep your vehicle from using excess fuel.
Engine spitting and sputtering is also a common sign of a bad throttle position sensor.