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Discussion Starter · #1 ·
Hi, my name is Chris, and I have a Dodge Charger Rt 2011 with 49k miles, just replaced the battery a day ago, all new spark plugs, and it seems like I have some sorta rev or acceleration issue, if I were to first start up the car and rev it, the rev goes down quickly, but after sometime when the car is warmed up, the rev goes down slow, or it just sits at the high RPM for a second and slowly drops, and sometimes when I accelerate, the car has some sorta jerk, like where it stops itself and then it starts accelerating. Should I try and reset the throttle or calibrate the throttle, or is that feature not available on my car? Or how should I fix this issue?
 

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Should I try and reset the throttle or calibrate the throttle, or is that feature not available on my car?
You can try the throttle body calibration procedure to see if it makes any difference.
Push the ignition button to Run but do not start the engine (foot off the brake pedal). Wait until all the bells/whistle/chimes/lights stop doing their dance. Depress the gas pedal smoothly and quickly all the way to the floor ... as far as it will go ... and let it up (manual says within 10 seconds). Push the ignition to Off and you're done.
If you depress the pedal three times it resets the oil change monitor.

You can also plug a scanner into the car's OBD2 port to see if there's any pending codes logged. Since the problem seems to be intermittent there may be a pending code that has not been set to Active/Permanent. If there are any codes, and the scanner supports the feature, look to see if there's any Freeze Frame data stored.

Also check all the vacuum hoses for any leaks. Check the PCV valve to make sure it's not sticking. Check the air intake manifold bolts to see if they're loose. They should be torqued to 9 ft. lbs. If they're loose, tighten then in the following sequence.

Font Circle Auto part Engineering Drawing

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Discussion Starter · #3 ·
You can try the throttle body calibration procedure to see if it makes any difference.
Push the ignition button to Run but do not start the engine (foot off the brake pedal). Wait until all the bells/whistle/chimes/lights stop doing their dance. Depress the gas pedal smoothly and quickly all the way to the floor ... as far as it will go ... and let it up (manual says within 10 seconds). Push the ignition to Off and you're done.
If you depress the pedal three times it resets the oil change monitor.

You can also plug a scanner into the car's OBD2 port to see if there's any pending codes logged. Since the problem seems to be intermittent there may be a pending code that has not been set to Active/Permanent. If there are any codes, and the scanner supports the feature, look to see if there's any Freeze Frame data stored.

Also check all the vacuum hoses for any leaks. Check the PCV valve to make sure it's not sticking. Check the air intake manifold bolts to see if they're loose. They should be torqued to 9 ft. lbs. If they're loose, tighten then in the following sequence.

View attachment 301769
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Thankyou so much, so when I do the calibration, I should push it down all the way and then move up quickly but smoothly, and I don’t have to push the pedal down for a certain time right?
 

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Within the 10 seconds of time you should push the accelerator pedal all the way to the floor (as far is it will go) in a smooth continuous motion and then release the accelerator pedal in a smooth continuous motion. Only take your foot off the accelerator pedal after it has moved all the way back from the floor.
It's called the throttle body calibration procedure but it's really ETC (electronic throttle control) calibration. The PCM sends the 5V supply to the throttle body (TB) and the accelerator pedal position sensors (APPS). The PCM receives the APPS signal indicating the pedal position. The PCM sends a signal to the TB ETC motor to move the TB plate (aka butterfly) to match the position of the accelerator pedal. The PCM receives the throttle position sensor (TPS) signal from the TB indicating the position of the TB plate.
When you push/release the accelerator pedal, the full range of travel, the PCM is able to determine the APPS signal range and calibrate the position of the ETC motor (TB plate) accordingly.

Another item to check for your problem is the throttle plate. If the throttle plate is dirty it may stick and move in a jerky motion. Remove the air intake tube from the front of throttle body. Be careful of the intake air temp (IAT) sensor that's attached to the air intake tube ... the wires are not that rugged. Use throttle body cleaner (not carb cleaner or any other harsh cleaner) if the mouth of the throttle body or the throttle plate are dirty. Spray the cleaner with the throttle plate closed. Do not move the throttle plate or spray the cleaner past the throttle plate to the inside of the throttle body. The ETC motor and other electronics are inside the throttle body and can get damaged. Wipe everything clean and dry and reconnect the air intake tube.
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Discussion Starter · #5 ·
Within the 10 seconds of time you should push the accelerator pedal all the way to the floor (as far is it will go) in a smooth continuous motion and then release the accelerator pedal in a smooth continuous motion. Only take your foot off the accelerator pedal after it has moved all the way back from the floor.
It's called the throttle body calibration procedure but it's really ETC (electronic throttle control) calibration. The PCM sends the 5V supply to the throttle body (TB) and the accelerator pedal position sensors (APPS). The PCM receives the APPS signal indicating the pedal position. The PCM sends a signal to the TB ETC motor to move the TB plate (aka butterfly) to match the position of the accelerator pedal. The PCM receives the throttle position sensor (TPS) signal from the TB indicating the position of the TB plate.
When you push/release the accelerator pedal, the full range of travel, the PCM is able to determine the APPS signal range and calibrate the position of the ETC motor (TB plate) accordingly.

Another item to check for your problem is the throttle plate. If the throttle plate is dirty it may stick and move in a jerky motion. Remove the air intake tube from the front of throttle body. Be careful of the intake air temp (IAT) sensor that's attached to the air intake tube ... the wires are not that rugged. Use throttle body cleaner (not carb cleaner or any other harsh cleaner) if the mouth of the throttle body or the throttle plate are dirty. Spray the cleaner with the throttle plate closed. Do not move the throttle plate or spray the cleaner past the throttle plate to the inside of the throttle body. The ETC motor and other electronics are inside the throttle body and can get damaged. Wipe everything clean and dry and reconnect the air intake tube.
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Okay Thankyou so much, I will take a look at the throttle plate, that might resolve my issue!
 

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I forgot to mention that in addition to not using any carb cleaner on the throttle body ... do not apply silicone lubricants to any part of the throttle body.
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Should it be somewhat open like that when the car is off?
Yes. It should be open at an angle of about 7.5° when it's in the fully closed position. This small partial opening of the throttle plate provides enough air flow to allow the engine to run at idle in the absence of any throttle control. It allows the car to crawl along at idle speed so the driver can continue driving to a safe place; also referred to as Limp Home mode.
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Discussion Starter · #10 ·
Yes. It should be open at an angle of about 7.5° when it's in the fully closed position. This small partial opening of the throttle plate provides enough air flow to allow the engine to run at idle in the absence of any throttle control. It allows the car to crawl along at idle speed so the driver can continue driving to a safe place; also referred to as Limp Home mode.
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Then that’s weird, I don’t know why my car is acting like this, should I take it to a dealership?
 

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Dealership can run their diagnostics system and see if something else is wrong.
 
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