RPMs jump like the TPS is bad but is not?

2001 NISSAN SERENA
206,000 MILES • 1.8L • 4 CYL • 2WD • MANUAL
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THICK10X
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Car when started idle high, warms up and still idle high. Replaced MAF sensor, idle control valve, and cleaned throttle body. When given gas it falls on face and RPMs start to jump up and down…. doesn’t act like registering gas pedal. No check engine light on, Nissan couldn’t program or fix, idles at 1,800 RPMs and higher when cold…tested connections and ground, will start and run, but won’t accelerate.
Sep 8, 2022 at 8:22 PM
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STRAILER
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It sounds like it is in limp mode have you run the codes? Here is a guide to show you how to do a CAN scan which is easy, you can get a CAN scanner (Controller Area Network) from Amazon for about $30.00.

Here is a video to show you how:

https://youtu.be/u-4syLc-ifQ

Here is a scanner link:

https://amzn.to/3o41KcZ

I think the ECM has gone out which is common in these cars. Here is how you can change it out if the scan comes back and the unit is bad. Check out the images (below). Please let us know what happens.

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Sep 9, 2022 at 1:46 PM