When I press the gas pedal the engine revs but the car doesn’t accelerate. Is this a throttle or transmission issue?

ANSWER : Hi there. From what you are saying it sounds like there is a failure in the throttle body. When the motor in the throttle body fails, the throttle plate will open and close causing the noise you are hearing. I usually monitor the movement of the throttle to see if this is what is occurring. I then scan the computer for codes to see what comes up. If there are not any codes then the sensors in the throttle body should be monitored to see what is going wrong. If you want to have this lack of throttle response checked, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose and repair your throttle body issue.

ANSWER : Hello. It sounds like you may have an issue with your throttle position sensor. This sensor sends a reference voltage to your power-train control module, which uses that to determine ignition timing and fuel trims. If the power-train control module is not detecting the proper signal from the throttle position sensor, the engine may not accelerate properly. It’s probably a good idea for you to have a professional mobile mechanic come to your location and complete a car is slow to accelerate inspection first, so they can pinpoint what is causing this issue to occur and they will recommend the right repairs be completed.

ANSWER : Good question. I want to go through a few steps with you and hopefully find your problem and save you some time and money. If you find the issue during steps, then ahead and fix that fault and you should be fine.

First, open the hood and take the engine cover off if there is one. Take off your air intake hose. This should be connected to your air filter. If it is dirty on the inside where the mass air flow sensor (MAF) is, the MAF looks like a honey comb on the inside. When the tube is off and the car is off, ask someone to sit in the car and see if if you throttle body is opening and closing while the other person is pressing the gas. If not make sure the cable on the side are connected. If not reconnect them and try again. Hopefully this is your problem. If your cables are connected your cables are moving and your throttle body aren’t you may have something broken inside of your throttle body causing your throttle not to work properly.

If your cables are connected and not moving, you will need to check your pedals and find out where the disconnection is coming from. If all of this checks out try disconnecting your battery for 10-15 minutes and reconnect it. It could just not be reading that you are pressing the gas. Finally, you can check your fuses and ensure that none of them are blown.

If you would like to have an expert take care of this for you, a qualified professional from YourMechanic can come to your location to diagnose the car’s acceleration problem and guide you through proper repairs.

ANSWER : Knowing the results of the computer diagnosis as well as the part that was replaced can be helpful in assisting you with your Pontiac G3. It is possible the part that was replaced is defective and may need to be replaced. Based on what you described with your vehicle, it appears that you may be experiencing transmission issues.

The engine should never be revved up to six to seven thousand RPMs when the vehicle is not moving, as this can cause damage to the vehicle’s components. Because the information provided is a little unclear, it is hard to determine if you are having concerns with your transmission or if the problem lies with the engine itself.

If you don’t trust going back to the same mechanic that worked on your car originally, get yourself a second opinion and enlist the help of one of our certified mechanics who can diagnose why the Check Engine Light is on as well as determine why your Pontiac is not accelerating. They will also be able to assist you with the repairs needed to get your G3 up and running again.

ANSWER : Hello. If the car is in "Drive" and you attempt to accelerate from a standing start and yet the car does not move forward, you have a problem with the transmission (perhaps the linkages) and/or torque converter. The misfire code might be simply a coincidental issue because even if the engine is running "roughly" (i.e., misfiring) if you are in "Drive" the car will move. Your best bet is to have a certified technician, like one from YourMechanic, come to your home or office to diagnose the acceleration problem and advise you on repairs. It doesn’t sound like an "intermittent" problem at this point, so it should be fairly easy to discover what the issues are.

ANSWER : The manufacturer has a technical bulletin to cover this problem. They would first check for any standing transmission problems then reprogram the PCM power train control module to the latest levels. Get in touch with your dealer to have this problem addressed for you.

ANSWER : This loss of accelerator control is a built in safety feature of the vehicle computer and can render the throttle inactive if it sees a problem in a major component or loses communication with the throttle sensor.

I have even seen where the brakes being on at the same time you try to push the throttle the computer will not let you accelerate. This can happen if you use two feet to drive and rest your foot on the brake while driving and the computer thinks you want to stop at the same time accelerate. The computer will take the brake signal and not let you accelerate.

Recommend having the Check Engine Light scanned by a certified technician, like one from YourMechanic, to see if there is codes that need diagnosed or try not to touch the brake at the same time accelerating.

ANSWER : Hello, thank you for writing in. The engine is likely sensing an issue and compensating for it. When you restart the vehicle, the component may be passing its start up tests, and the engine stops trying to outperform itself. Start by having the vehicle scanned for diagnostic codes. If there is another sensor to blame, it may show up there and make diagnostics a lot easier. If not codes come up, you will want to test the fuel pressure available at the engine, and make sure the fuel system is working properly. You can also clean the throttle and test the throttle position sensor. For more help with diagnosing and resolving the issue, contact our service department to schedule an appointment.