Code P2138?

2009 CHEVROLET IMPALA
120,000 MILES • 3.9L • V6 • 2WD • AUTOMATIC
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EZEX
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My car keeps throwing code p2138 and going into limp home mode. Even when it's not throwing it the engine feels off and doesn't want to rev. It's noticeably worse in the morning on cold starts. Then it refuses to clear the code. Once it's warm it tends to clear for a while.

I've replaced the throttle body and the accelerator pedal. Didn't solve anything.
Nov 22, 2022 at 9:10 AM
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STRAILER
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The code P2138 - throttle body position sensor and accelerator pedal position sensor do not match. When you say the accelerator pedal do you mean the accelerator pedal sensor? Also were they new parts? If so, you may have a PCM going out which can cause these codes as well. Here is how to change out the PCM in the images below, you can get a rebuilt unit by searching Google or Ebay, have your VIN number ready. This should not be a wiring problem because the code is not a circuit error. The rebuilt PCM will come preprogrammed. Check out the images (below). Please let us know what happens. Also, you can remove the electrical connectors for the PCM and check them for corrosion.
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Nov 23, 2022 at 12:08 PM
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EZEX
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If I get a PCM that isn't programmed, how do I program it?
Dec 14, 2022 at 8:29 AM
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STRAILER
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You will need a bidirectional scanner or have the rebuilder program it for you.
Dec 15, 2022 at 3:26 PM